2.4.0.82443402 - Disclosure - Fair Value Measurements Fair Value Measurements (Details)truefalseIn Thousands, unless otherwise specifiedfalse1false USDfalsefalse$I2013Q2_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00ratioStandardhttp://www.xbrl.org/2003/instancepurexbrli0usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$2false USDfalsefalse$I2012Q4_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMemberhttp://www.sec.gov/CIK0000731657instant2012-12-31T00:00:000001-01-01T00:00:00ratioStandardhttp://www.xbrl.org/2003/instancepurexbrli0usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$1true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]2false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse32110003211USD$falsetruefalse2truefalsefalse29630002963USD$falsetruefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure3false 5spir_PercentOfTotalAvailableForSaleInvestmentsspir_falsenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse1.001.00falsefalsefalse2truetruefalse1.001.00falsefalsefalsenum:percentItemTypepurePercent of Total Available-for-sale InvestmentsNo definition available.false0Percent of Total Available-for-sale Investments4false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel1Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseFair Value, Inputs, Level 1 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberratioStandardhttp://www.xbrl.org/2003/instancepurexbrli0usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Fair Value, Inputs, Level 1 [Member]5true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]6false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse17080001708USD$falsefalsefalse2truefalsefalse12650001265USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure7false 5spir_PercentOfTotalAvailableForSaleInvestmentsspir_falsenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.530.53falsefalsefalse2truetruefalse0.430.43falsefalsefalsenum:percentItemTypepurePercent of Total Available-for-sale InvestmentsNo definition available.false0Percent of Total Available-for-sale Investments8false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse5false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel2Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseFair Value, Inputs, Level 2 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberratioStandardhttp://www.xbrl.org/2003/instancepurexbrli0usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Fair Value, Inputs, Level 2 [Member]9true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]10false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse15030001503USD$falsefalsefalse2truefalsefalse16980001698USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure11false 5spir_PercentOfTotalAvailableForSaleInvestmentsspir_falsenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.470.47falsefalsefalse2truetruefalse0.570.57falsefalsefalsenum:percentItemTypepurePercent of Total Available-for-sale InvestmentsNo definition available.false0Percent of Total Available-for-sale Investments12false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse7false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseFair Value, Inputs, Level 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberratioStandardhttp://www.xbrl.org/2003/instancepurexbrli0usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Fair Value, Inputs, Level 3 [Member]13true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]14false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure15false 5spir_PercentOfTotalAvailableForSaleInvestmentsspir_falsenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.000.00falsefalsefalse2truetruefalse0.000.00falsefalsefalsenum:percentItemTypepurePercent of Total Available-for-sale InvestmentsNo definition available.false0Percent of Total Available-for-sale Investments16false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse9false USDtruefalse$I2013Q2_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CashAndCashEquivalentsMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCash and Cash Equivalents [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CashAndCashEquivalentsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Cash and Cash Equivalents [Member]17true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]18false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse7000070USD$falsefalsefalse2truefalsefalse3200032USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure19false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse11false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel1Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CashAndCashEquivalentsMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCash and Cash Equivalents [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CashAndCashEquivalentsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member]20true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]21false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse7000070USD$falsefalsefalse2truefalsefalse3200032USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure22false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse13false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel2Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CashAndCashEquivalentsMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCash and Cash Equivalents [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CashAndCashEquivalentsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member]23true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]24false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure25false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse15false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CashAndCashEquivalentsMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCash and Cash Equivalents [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CashAndCashEquivalentsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 3 [Member]26true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]27false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure28false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse17false USDtruefalse$I2013Q2_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member]29true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]30false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse13590001359USD$falsefalsefalse2truefalsefalse708000708USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure31false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse19false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel1Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Fair Value, Inputs, Level 1 [Member]32true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]33false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse13590001359USD$falsefalsefalse2truefalsefalse708000708USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure34false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse21false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel2Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Fair Value, Inputs, Level 2 [Member]35true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]36false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure37false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse23false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Fair Value, Inputs, Level 3 [Member]38true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]39false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure40false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse25false USDtruefalse$I2013Q2_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_BasicMaterialMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseBasic Material [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_BasicMaterialMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Basic Material [Member]41true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]42false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse2800028USD$falsefalsefalse2truefalsefalse1500015USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure43false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse27false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel1Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_BasicMaterialMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseBasic Material [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_BasicMaterialMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Basic Material [Member] | Fair Value, Inputs, Level 1 [Member]44true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]45false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse2800028USD$falsefalsefalse2truefalsefalse1500015USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure46false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse29false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel2Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_BasicMaterialMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseBasic Material [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_BasicMaterialMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Basic Material [Member] | Fair Value, Inputs, Level 2 [Member]47true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]48false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure49false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse31false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_BasicMaterialMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseBasic Material [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_BasicMaterialMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Basic Material [Member] | Fair Value, Inputs, Level 3 [Member]50true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]51false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure52false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse33false USDtruefalse$I2013Q2_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_ConsumerGoodsMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseconsumer goods [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_ConsumerGoodsMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | consumer goods [Member]53true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]54false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse126000126USD$falsefalsefalse2truefalsefalse5800058USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure55false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse35false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel1Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_ConsumerGoodsMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseconsumer goods [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_ConsumerGoodsMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | consumer goods [Member] | Fair Value, Inputs, Level 1 [Member]56true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]57false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse126000126USD$falsefalsefalse2truefalsefalse5800058USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure58false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse37false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel2Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_ConsumerGoodsMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseconsumer goods [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_ConsumerGoodsMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | consumer goods [Member] | Fair Value, Inputs, Level 2 [Member]59true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]60false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure61false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse39false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_ConsumerGoodsMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseconsumer goods [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_ConsumerGoodsMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | consumer goods [Member] | Fair Value, Inputs, Level 3 [Member]62true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]63false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure64false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse41false USDtruefalse$I2013Q2_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_EnergyMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseEnergy [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_EnergyMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Energy [Member]65true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]66false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse124000124USD$falsefalsefalse2truefalsefalse2900029USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure67false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse43false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel1Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_EnergyMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseEnergy [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_EnergyMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Energy [Member] | Fair Value, Inputs, Level 1 [Member]68true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]69false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse124000124USD$falsefalsefalse2truefalsefalse2900029USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure70false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse45false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel2Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_EnergyMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseEnergy [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_EnergyMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Energy [Member] | Fair Value, Inputs, Level 2 [Member]71true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]72false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure73false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse47false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_EnergyMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseEnergy [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_EnergyMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Energy [Member] | Fair Value, Inputs, Level 3 [Member]74true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]75false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure76false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse49false USDtruefalse$I2013Q2_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_FinancialMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseFinancial [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_FinancialMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Financial [Member]77true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]78false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse114000114USD$falsefalsefalse2truefalsefalse6100061USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure79false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse51false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel1Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_FinancialMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseFinancial [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_FinancialMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Financial [Member] | Fair Value, Inputs, Level 1 [Member]80true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]81false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse114000114USD$falsefalsefalse2truefalsefalse6100061USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure82false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse53false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel2Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_FinancialMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseFinancial [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_FinancialMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Financial [Member] | Fair Value, Inputs, Level 2 [Member]83true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]84false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure85false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse55false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_FinancialMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseFinancial [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_FinancialMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Financial [Member] | Fair Value, Inputs, Level 3 [Member]86true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]87false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure88false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse57false USDtruefalse$I2013Q2_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_HealthcareMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseHealthcare [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_HealthcareMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Healthcare [Member]89true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]90false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse140000140USD$falsefalsefalse2truefalsefalse5200052USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure91false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse59false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel1Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_HealthcareMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseHealthcare [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_HealthcareMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Healthcare [Member] | Fair Value, Inputs, Level 1 [Member]92true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]93false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse140000140USD$falsefalsefalse2truefalsefalse5200052USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure94false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse61false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel2Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_HealthcareMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseHealthcare [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_HealthcareMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Healthcare [Member] | Fair Value, Inputs, Level 2 [Member]95true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]96false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure97false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse63false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_HealthcareMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseHealthcare [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_HealthcareMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Healthcare [Member] | Fair Value, Inputs, Level 3 [Member]98true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]99false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure100false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse65false USDtruefalse$I2013Q2_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_IndustrialGoodsMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseIndustrial Goods [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_IndustrialGoodsMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Industrial Goods [Member]101true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]102false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse141000141USD$falsefalsefalse2truefalsefalse5100051USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure103false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse67false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel1Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_IndustrialGoodsMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseIndustrial Goods [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_IndustrialGoodsMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Industrial Goods [Member] | Fair Value, Inputs, Level 1 [Member]104true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]105false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse141000141USD$falsefalsefalse2truefalsefalse5100051USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure106false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse69false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel2Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_IndustrialGoodsMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseIndustrial Goods [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_IndustrialGoodsMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Industrial Goods [Member] | Fair Value, Inputs, Level 2 [Member]107true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]108false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure109false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse71false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_IndustrialGoodsMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseIndustrial Goods [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_IndustrialGoodsMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Industrial Goods [Member] | Fair Value, Inputs, Level 3 [Member]110true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]111false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure112false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse73false USDtruefalse$I2013Q2_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_ServicesMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseServices [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_ServicesMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Services [Member]113true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]114false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse5400054USD$falsefalsefalse2truefalsefalse3200032USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure115false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse75false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel1Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_ServicesMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseServices [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_ServicesMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Services [Member] | Fair Value, Inputs, Level 1 [Member]116true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]117false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse5400054USD$falsefalsefalse2truefalsefalse3200032USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure118false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse77false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel2Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_ServicesMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseServices [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_ServicesMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Services [Member] | Fair Value, Inputs, Level 2 [Member]119true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]120false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure121false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse79false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_ServicesMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseServices [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_ServicesMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Services [Member] | Fair Value, Inputs, Level 3 [Member]122true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]123false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure124false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse81false USDtruefalse$I2013Q2_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_TechnologyMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseTechnology [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_TechnologyMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Technology [Member]125true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]126false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse607000607USD$falsefalsefalse2truefalsefalse376000376USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure127false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse83false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel1Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_TechnologyMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseTechnology [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_TechnologyMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Technology [Member] | Fair Value, Inputs, Level 1 [Member]128true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]129false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse607000607USD$falsefalsefalse2truefalsefalse376000376USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure130false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse85false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel2Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_TechnologyMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseTechnology [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_TechnologyMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Technology [Member] | Fair Value, Inputs, Level 2 [Member]131true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]132false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure133false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse87false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_TechnologyMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseTechnology [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_TechnologyMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Technology [Member] | Fair Value, Inputs, Level 3 [Member]134true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]135false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure136false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse89false USDtruefalse$I2013Q2_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_TransportationMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseTransportation [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_TransportationMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Transportation [Member]137true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]138false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse90009USD$falsefalsefalse2truefalsefalse80008USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure139false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse91false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel1Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_TransportationMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseTransportation [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_TransportationMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Transportation [Member] | Fair Value, Inputs, Level 1 [Member]140true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]141false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse90009USD$falsefalsefalse2truefalsefalse80008USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure142false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse93false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel2Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_TransportationMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseTransportation [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_TransportationMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Transportation [Member] | Fair Value, Inputs, Level 2 [Member]143true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]144false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure145false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse95false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_TransportationMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseTransportation [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_TransportationMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Transportation [Member] | Fair Value, Inputs, Level 3 [Member]146true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]147false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure148false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse97false USDtruefalse$I2013Q2_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_UtilitiesMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseUtilities [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_UtilitiesMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Utilities [Member]149true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]150false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse1600016USD$falsefalsefalse2truefalsefalse2600026USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure151false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse99false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel1Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_UtilitiesMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseUtilities [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_UtilitiesMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Utilities [Member] | Fair Value, Inputs, Level 1 [Member]152true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]153false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse1600016USD$falsefalsefalse2truefalsefalse2600026USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure154false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse101false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel2Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_UtilitiesMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseUtilities [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_UtilitiesMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Utilities [Member] | Fair Value, Inputs, Level 2 [Member]155true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]156false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure157false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse103false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_CommonStockMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_UtilitiesMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCommon Stock [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseUtilities [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_UtilitiesMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Common Stock [Member] | Utilities [Member] | Fair Value, Inputs, Level 3 [Member]158true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]159false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure160false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse105false USDtruefalse$I2013Q2_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member]161true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]162false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse12650001265USD$falsefalsefalse2truefalsefalse15270001527USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure163false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse107false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel1Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member] | Fair Value, Inputs, Level 1 [Member]164true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]165false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse279000279USD$falsefalsefalse2truefalsefalse525000525USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure166false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse109false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel2Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member] | Fair Value, Inputs, Level 2 [Member]167true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]168false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse986000986USD$falsefalsefalse2truefalsefalse10020001002USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure169false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse111false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member] | Fair Value, Inputs, Level 3 [Member]170true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]171false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure172false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse113false USDtruefalse$I2013Q2_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_DiversifiedEmergencyMarketMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseDiversified Emergency Market [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_DiversifiedEmergencyMarketMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member] | Diversified Emergency Market [Member]173true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]174false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse230000230USD$falsefalsefalse2truefalsefalse187000187USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure175false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse115false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel1Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_DiversifiedEmergencyMarketMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseDiversified Emergency Market [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_DiversifiedEmergencyMarketMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member] | Diversified Emergency Market [Member] | Fair Value, Inputs, Level 1 [Member]176true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]177false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure178false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse117false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel2Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_DiversifiedEmergencyMarketMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseDiversified Emergency Market [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_DiversifiedEmergencyMarketMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member] | Diversified Emergency Market [Member] | Fair Value, Inputs, Level 2 [Member]179true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]180false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse230000230USD$falsefalsefalse2truefalsefalse187000187USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure181false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse119false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_DiversifiedEmergencyMarketMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseDiversified Emergency Market [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_DiversifiedEmergencyMarketMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member] | Diversified Emergency Market [Member] | Fair Value, Inputs, Level 3 [Member]182true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]183false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure184false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse121false USDtruefalse$I2013Q2_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_ForeignLargeBlendMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseForeign Large Blend [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_ForeignLargeBlendMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member] | Foreign Large Blend [Member]185true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]186false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse239000239USD$falsefalsefalse2truefalsefalse244000244USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure187false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse123false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel1Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_ForeignLargeBlendMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseForeign Large Blend [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_ForeignLargeBlendMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member] | Foreign Large Blend [Member] | Fair Value, Inputs, Level 1 [Member]188true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]189false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure190false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse125false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel2Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_ForeignLargeBlendMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseForeign Large Blend [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_ForeignLargeBlendMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member] | Foreign Large Blend [Member] | Fair Value, Inputs, Level 2 [Member]191true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]192false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse239000239USD$falsefalsefalse2truefalsefalse244000244USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure193false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse127false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_ForeignLargeBlendMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseForeign Large Blend [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_ForeignLargeBlendMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member] | Foreign Large Blend [Member] | Fair Value, Inputs, Level 3 [Member]194true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]195false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure196false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse129false USDtruefalse$I2013Q2_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_ForeignLargeGrowthMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseForeign Large Growth [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_ForeignLargeGrowthMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member] | Foreign Large Growth [Member]197true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]198false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse233000233USD$falsefalsefalse2truefalsefalse250000250USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure199false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse131false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel1Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_ForeignLargeGrowthMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseForeign Large Growth [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_ForeignLargeGrowthMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member] | Foreign Large Growth [Member] | Fair Value, Inputs, Level 1 [Member]200true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]201false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure202false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse133false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel2Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_ForeignLargeGrowthMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseForeign Large Growth [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_ForeignLargeGrowthMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member] | Foreign Large Growth [Member] | Fair Value, Inputs, Level 2 [Member]203true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]204false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse233000233USD$falsefalsefalse2truefalsefalse250000250USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure205false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse135false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_ForeignLargeGrowthMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseForeign Large Growth [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_ForeignLargeGrowthMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member] | Foreign Large Growth [Member] | Fair Value, Inputs, Level 3 [Member]206true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]207false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure208false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse137false USDtruefalse$I2013Q2_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_GlobalHighYieldIncomeFundMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseGlobal High Yield Income Fund [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_GlobalHighYieldIncomeFundMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member] | Global High Yield Income Fund [Member]209true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]210false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse5200052USD$falsefalsefalse2truefalsefalse5200052USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure211false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse139false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel1Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_GlobalHighYieldIncomeFundMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseGlobal High Yield Income Fund [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_GlobalHighYieldIncomeFundMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member] | Global High Yield Income Fund [Member] | Fair Value, Inputs, Level 1 [Member]212true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]213false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure214false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse141false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel2Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_GlobalHighYieldIncomeFundMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseGlobal High Yield Income Fund [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_GlobalHighYieldIncomeFundMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member] | Global High Yield Income Fund [Member] | Fair Value, Inputs, Level 2 [Member]215true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]216false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse5200052USD$falsefalsefalse2truefalsefalse5200052USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure217false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse143false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_GlobalHighYieldIncomeFundMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseGlobal High Yield Income Fund [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_GlobalHighYieldIncomeFundMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member] | Global High Yield Income Fund [Member] | Fair Value, Inputs, Level 3 [Member]218true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]219false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure220false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse145false USDtruefalse$I2013Q2_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_LargeGrowthMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseLarge Growth [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_LargeGrowthMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member] | Large Growth [Member]221true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]222false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse232000232USD$falsefalsefalse2truefalsefalse220000220USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure223false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse147false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel1Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_LargeGrowthMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseLarge Growth [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_LargeGrowthMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member] | Large Growth [Member] | Fair Value, Inputs, Level 1 [Member]224true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]225false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure226false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse149false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel2Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_LargeGrowthMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseLarge Growth [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_LargeGrowthMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member] | Large Growth [Member] | Fair Value, Inputs, Level 2 [Member]227true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]228false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse232000232USD$falsefalsefalse2truefalsefalse220000220USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure229false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse151false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_LargeGrowthMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseLarge Growth [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_LargeGrowthMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member] | Large Growth [Member] | Fair Value, Inputs, Level 3 [Member]230true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]231false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure232false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse153false USDtruefalse$I2012Q4_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_PreciousMetalsMemberhttp://www.sec.gov/CIK0000731657instant2012-12-31T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalsePrecious Metals [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_PreciousMetalsMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member] | Precious Metals [Member]233true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]234false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2truefalsefalse4900049USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure235false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse154false USDtruefalse$I2012Q4_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel1Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_PreciousMetalsMemberhttp://www.sec.gov/CIK0000731657instant2012-12-31T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalsePrecious Metals [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_PreciousMetalsMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member] | Precious Metals [Member] | Fair Value, Inputs, Level 1 [Member]236true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]237false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure238false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse155false USDtruefalse$I2012Q4_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel2Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_PreciousMetalsMemberhttp://www.sec.gov/CIK0000731657instant2012-12-31T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalsePrecious Metals [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_PreciousMetalsMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member] | Precious Metals [Member] | Fair Value, Inputs, Level 2 [Member]239true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]240false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2truefalsefalse4900049USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure241false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse156false USDtruefalse$I2012Q4_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_PreciousMetalsMemberhttp://www.sec.gov/CIK0000731657instant2012-12-31T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalsePrecious Metals [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_PreciousMetalsMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member] | Precious Metals [Member] | Fair Value, Inputs, Level 3 [Member]242true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]243false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure244false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse157false USDtruefalse$I2013Q2_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_SmallBlendMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseSmall Blend [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_SmallBlendMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member] | Small Blend [Member]245true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]246false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse279000279USD$falsefalsefalse2truefalsefalse525000525USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure247false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse159false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel1Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_SmallBlendMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseSmall Blend [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_SmallBlendMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member] | Small Blend [Member] | Fair Value, Inputs, Level 1 [Member]248true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]249false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse279000279USD$falsefalsefalse2truefalsefalse525000525USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure250false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse161false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel2Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_SmallBlendMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseSmall Blend [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_SmallBlendMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member] | Small Blend [Member] | Fair Value, Inputs, Level 2 [Member]251true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]252false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure253false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse163false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_EquityFundsMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_spir_SmallBlendMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseEquity Funds [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquityFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseSmall Blend [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldispir_SmallBlendMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Equity Funds [Member] | Small Blend [Member] | Fair Value, Inputs, Level 3 [Member]254true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]255false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure256false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse165false USDtruefalse$I2013Q2_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_DebtSecuritiesMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseDebt Securities [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DebtSecuritiesMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Debt Securities [Member]257true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]258false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse517000517USD$falsefalsefalse2truefalsefalse696000696USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure259false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse167false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel1Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_DebtSecuritiesMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseDebt Securities [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DebtSecuritiesMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member]260true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]261false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure262false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse169false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel2Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_DebtSecuritiesMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseDebt Securities [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DebtSecuritiesMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]263true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]264false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse517000517USD$falsefalsefalse2truefalsefalse696000696USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure265false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse171false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_DebtSecuritiesMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseDebt Securities [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DebtSecuritiesMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member]266true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]267false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure268false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse173false USDtruefalse$I2013Q2_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_DebtSecuritiesMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_us-gaap_DomesticCorporateDebtSecuritiesMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseDebt Securities [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DebtSecuritiesMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseDomestic Corporate Debt Securities [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticCorporateDebtSecuritiesMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Debt Securities [Member] | Domestic Corporate Debt Securities [Member]269true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]270false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse466000466USD$falsefalsefalse2truefalsefalse678000678USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure271false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse175false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel1Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_DebtSecuritiesMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_us-gaap_DomesticCorporateDebtSecuritiesMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseDebt Securities [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DebtSecuritiesMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseDomestic Corporate Debt Securities [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticCorporateDebtSecuritiesMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Debt Securities [Member] | Domestic Corporate Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member]272true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]273false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure274false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse177false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel2Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_DebtSecuritiesMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_us-gaap_DomesticCorporateDebtSecuritiesMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseDebt Securities [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DebtSecuritiesMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseDomestic Corporate Debt Securities [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticCorporateDebtSecuritiesMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Debt Securities [Member] | Domestic Corporate Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]275true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]276false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse466000466USD$falsefalsefalse2truefalsefalse678000678USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure277false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse179false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_DebtSecuritiesMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_us-gaap_DomesticCorporateDebtSecuritiesMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseDebt Securities [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DebtSecuritiesMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseDomestic Corporate Debt Securities [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticCorporateDebtSecuritiesMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Debt Securities [Member] | Domestic Corporate Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member]278true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]279false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure280false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse181false USDtruefalse$I2013Q2_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_DebtSecuritiesMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_us-gaap_ForeignCorporateDebtSecuritiesMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseDebt Securities [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DebtSecuritiesMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseForeign Corporate Debt Securities [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignCorporateDebtSecuritiesMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Debt Securities [Member] | Foreign Corporate Debt Securities [Member]281true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]282false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse5100051USD$falsefalsefalse2truefalsefalse1800018USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure283false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse183false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel1Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_DebtSecuritiesMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_us-gaap_ForeignCorporateDebtSecuritiesMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseDebt Securities [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DebtSecuritiesMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseForeign Corporate Debt Securities [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignCorporateDebtSecuritiesMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Debt Securities [Member] | Foreign Corporate Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member]284true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]285false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure286false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse185false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel2Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_DebtSecuritiesMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_us-gaap_ForeignCorporateDebtSecuritiesMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseDebt Securities [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DebtSecuritiesMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseForeign Corporate Debt Securities [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignCorporateDebtSecuritiesMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Debt Securities [Member] | Foreign Corporate Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]287true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]288false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse5100051USD$falsefalsefalse2truefalsefalse1800018USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosure289false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse187false USDtruefalse$I2013Q2_us-gaap_FairValueByFairValueHierarchyLevelAxis_us-gaap_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_InvestmentTypeAxis_us-gaap_DebtSecuritiesMember_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_us-gaap_ForeignCorporateDebtSecuritiesMemberhttp://www.sec.gov/CIK0000731657instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseDebt Securities [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DebtSecuritiesMemberus-gaap_InvestmentTypeAxisexplicitMemberfalsefalseForeign Corporate Debt Securities [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignCorporateDebtSecuritiesMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseFair Value, Measurements, Recurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Debt Securities [Member] | Foreign Corporate Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member]290true 4us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]291false 5us-gaap_AvailableForSaleSecuritiesFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsetruefalse2truefalsefalse00USD$falsetruefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 false2Available-for-sale Securities, Fair Value disclosurefalseFair Value Measurements Fair Value Measurements (Details) (Fair Value, Measurements, Recurring [Member], USD $)ThousandsUnKnownUnKnownUnKnowntruefalsefalseSheethttp://www.spirecorp.com/role/FairValueMeasurementsFairValueMeasurementsDetails2291