2.4.0.840432 - Disclosure - Investments In Unconsolidated Joint Ventures (Hillsborough 206 Holdings, L.L.C.) (Narrative) (Details)truefalsefalse1false falsefalseDuration_1_1_2013_To_6_30_2013_us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_cli_HillsboroughTwoHundredSixHoldingsLLCMemberhttp://www.sec.gov/CIK0000924901duration2013-01-01T00:00:002013-06-30T00:00:002false falsefalseAs_Of_10_23_2012_us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_cli_HillsboroughTwoHundredSixHoldingsLLCMemberhttp://www.sec.gov/CIK0000924901instant2012-10-23T00:00:000001-01-01T00:00:00Unit16Standardhttp://www.xbrl.org/2003/instancepurexbrli01false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse1false truefalseDuration_1_1_2013_To_6_30_2013_us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_cli_HillsboroughTwoHundredSixHoldingsLLCMemberhttp://www.sec.gov/CIK0000924901duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseHillsborough 206 Holdings, L.L.C. [Member]us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxisxbrldihttp://xbrl.org/2006/xbrldicli_HillsboroughTwoHundredSixHoldingsLLCMemberus-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxisexplicitMembernanafalse0Hillsborough 206 Holdings, L.L.C. [Member]2true 3us-gaap_ScheduleOfEquityMethodInvestmentsLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Schedule of Equity Method Investments [Line Items]3false 4us-gaap_EquityMethodInvestmentOwnershipPercentageus-gaap_truenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2truetruefalse0.500.50falsefalsefalsenum:percentItemTypepureThe percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 159 -Paragraph 18 -Subparagraph f -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 18 -Paragraph 20 -Subparagraph a (1) -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. false0Percentage of interest in venture4false 4cli_HoldingAndDistributionPatternUnderOperatingAgreementcli_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00The operating agreement of Hillsborough 206 provides, among other things, for the distribution of distributable cash to the members, in accordance with their ownership percentages.falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringHolding And Distribution Pattern Under Operating AgreementNo definition available.false0Holding and distribution pattern under operating agreementfalseInvestments In Unconsolidated Joint Ventures (Hillsborough 206 Holdings, L.L.C.) (Narrative) (Details) (Hillsborough 206 Holdings, L.L.C. [Member])UnKnownUnKnownUnKnownUnKnowntruefalsefalseSheethttp://www.mack-cali.com/role/DisclosureInvestmentsInUnconsolidatedJointVenturesHillsborough206HoldingsLLCNarrativeDetails24