2.4.0.8133 - Disclosure - Loans - Summary of Troubled Debt Restructurings (Detail)truefalseIn Thousands, unless otherwise specifiedfalse1false USDfalsefalse$eol_PE10141---1310-Q0004_STD_91_20130630_0http://www.sec.gov/CIK0000880417duration2013-04-01T00:00:002013-06-30T00:00:00ContractStandardhttp://www.csb1.com/20130630Contractcsbb0iso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$2false USDfalsefalse$eol_PE10141---1310-Q0004_STD_91_20120630_0http://www.sec.gov/CIK0000880417duration2012-04-01T00:00:002012-06-30T00:00:00ContractStandardhttp://www.csb1.com/20130630Contractcsbb0iso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$3false USDfalsefalse$eol_PE10141---1310-Q0004_STD_181_20130630_0http://www.sec.gov/CIK0000880417duration2013-01-01T00:00:002013-06-30T00:00:00ContractStandardhttp://www.csb1.com/20130630Contractcsbb0iso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$4false USDfalsefalse$eol_PE10141---1310-Q0004_STD_182_20120630_0http://www.sec.gov/CIK0000880417duration2012-01-01T00:00:002012-06-30T00:00:00ContractStandardhttp://www.csb1.com/20130630Contractcsbb0iso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$1true 3us-gaap_FinancingReceivableModificationsLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Financing Receivable, Modifications [Line Items]2false 4us-gaap_FinancingReceivableModificationsNumberOfContracts2us-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse22falsefalsefalse2truefalsefalse66falsefalsefalse3truefalsefalse22falsefalsefalse4truefalsefalse88falsefalsefalsexbrli:integerItemTypeintegerNumber of financing receivables that have been modified by troubled debt restructurings.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953676-111524 false256Number of loans restructured3false 4us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2us-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse7600076USD$falsetruefalse2truefalsefalse473000473USD$falsetruefalse3truefalsefalse7600076USD$falsetruefalse4truefalsefalse628000628USD$falsetruefalsexbrli:monetaryItemTypemonetaryPre-modification amount of investment in financing receivables modified by troubled debt restructurings.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953676-111524 false2Pre- Modification Recorded Investment4false 4us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2us-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse7600076USD$falsefalsefalse2truefalsefalse473000473USD$falsefalsefalse3truefalsefalse7600076USD$falsefalsefalse4truefalsefalse628000628USD$falsefalsefalsexbrli:monetaryItemTypemonetaryPost-modification amount of investment in financing receivables modified by troubled debt restructurings.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953676-111524 false2Post- Modification Recorded Investment5false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5false USDtruefalse$eol_PE10141---1310-Q0004_STD_91_20130630_0_930901x924326http://www.sec.gov/CIK0000880417duration2013-04-01T00:00:002013-06-30T00:00:00falsefalseCommercial [Member]us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommercialPortfolioSegmentMemberus-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxisexplicitMemberContractStandardhttp://www.csb1.com/20130630Contractcsbb0iso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Commercial [Member]6true 3us-gaap_FinancingReceivableModificationsLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Financing Receivable, Modifications [Line Items]7false 4us-gaap_FinancingReceivableModificationsNumberOfContracts2us-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse22falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse22falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:integerItemTypeintegerNumber of financing receivables that have been modified by troubled debt restructurings.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953676-111524 false256Number of loans restructured8false 4us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2us-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse7600076USD$falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse7600076USD$falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryPre-modification amount of investment in financing receivables modified by troubled debt restructurings.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953676-111524 false2Pre- Modification Recorded Investment9false 4us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2us-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse7600076USD$falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse7600076USD$falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryPost-modification amount of investment in financing receivables modified by troubled debt restructurings.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953676-111524 false2Post- Modification Recorded Investment10false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse7false USDtruefalse$eol_PE10141---1310-Q0004_STD_91_20120630_0_930901x929810http://www.sec.gov/CIK0000880417duration2012-04-01T00:00:002012-06-30T00:00:00falsefalseResidential Real Estate [Member]us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ResidentialPortfolioSegmentMemberus-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxisexplicitMemberContractStandardhttp://www.csb1.com/20130630Contractcsbb0iso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Residential Real Estate [Member]11true 3us-gaap_FinancingReceivableModificationsLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Financing Receivable, Modifications [Line Items]12false 4us-gaap_FinancingReceivableModificationsNumberOfContracts2us-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2truefalsefalse55falsefalsefalse3falsefalsefalse00falsefalsefalse4truefalsefalse77falsefalsefalsexbrli:integerItemTypeintegerNumber of financing receivables that have been modified by troubled debt restructurings.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953676-111524 false256Number of loans restructured13false 4us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2us-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2truefalsefalse333000333USD$falsefalsefalse3falsefalsefalse00falsefalsefalse4truefalsefalse488000488USD$falsefalsefalsexbrli:monetaryItemTypemonetaryPre-modification amount of investment in financing receivables modified by troubled debt restructurings.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953676-111524 false2Pre- Modification Recorded Investment14false 4us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2us-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2truefalsefalse333000333USD$falsefalsefalse3falsefalsefalse00falsefalsefalse4truefalsefalse488000488USD$falsefalsefalsexbrli:monetaryItemTypemonetaryPost-modification amount of investment in financing receivables modified by troubled debt restructurings.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953676-111524 false2Post- Modification Recorded Investment15false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse9false USDtruefalse$eol_PE10141---1310-Q0004_STD_91_20120630_0_930901x927251http://www.sec.gov/CIK0000880417duration2012-04-01T00:00:002012-06-30T00:00:00falsefalseCommercial Real Estate [Member]us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommercialRealEstatePortfolioSegmentMemberus-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxisexplicitMemberContractStandardhttp://www.csb1.com/20130630Contractcsbb0iso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Commercial Real Estate [Member]16true 3us-gaap_FinancingReceivableModificationsLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Financing Receivable, Modifications [Line Items]17false 4us-gaap_FinancingReceivableModificationsNumberOfContracts2us-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2truefalsefalse11falsefalsefalse3falsefalsefalse00falsefalsefalse4truefalsefalse11falsefalsefalsexbrli:integerItemTypeintegerNumber of financing receivables that have been modified by troubled debt restructurings.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953676-111524 false256Number of loans restructured18false 4us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2us-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2truefalsefalse140000140USD$falsefalsefalse3falsefalsefalse00falsefalsefalse4truefalsefalse140000140USD$falsefalsefalsexbrli:monetaryItemTypemonetaryPre-modification amount of investment in financing receivables modified by troubled debt restructurings.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953676-111524 false2Pre- Modification Recorded Investment19false 4us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2us-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2truefalsefalse140000140USD$falsetruefalse3falsefalsefalse00falsefalsefalse4truefalsefalse140000140USD$falsetruefalsexbrli:monetaryItemTypemonetaryPost-modification amount of investment in financing receivables modified by troubled debt restructurings.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953676-111524 false2Post- Modification Recorded InvestmentfalseLoans - Summary of Troubled Debt Restructurings (Detail) (USD $)ThousandsUnKnownUnKnownUnKnowntruefalsefalseSheethttp://www.csb1.com/taxonomy/role/DisclosureLoansSummaryOfTroubledDebtRestructurings419