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This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 9 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=16385135&loc=d3e33749-111570 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.12) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 11 -Article 7 false2Equity in net loss from unconsolidated joint ventures24false 4gkk_TotalOperatingAndInterestExpensegkk_falsedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse-6957000-6957[1]USD$falsefalsefalse2truefalsefalse-8103000-8103[1]USD$falsefalsefalse3truefalsefalse-11691000-11691[1]USD$falsefalsefalse4truefalsefalse-13210000-13210[1]USD$falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryTotal operating and interest expense includes provision for loan losses for the Finance business and operating costs on commercial property assets for the realty business and as well as costs to perform required functions under the interim management agreement, and impairment charges relating to the company.No definition available.false2Total operating and interest expense25false 4us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterestus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse-6873000-6873[2]USD$falsefalsefalse2truefalsefalse-8050000-8050[2]USD$falsefalsefalse3truefalsefalse-11843000-11843[2]USD$falsefalsefalse4truefalsefalse-13087000-13087[2]USD$falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses and taxes from ongoing operations before extraordinary items, and noncontrolling interest.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 19 -URI http://asc.fasb.org/extlink&oid=7656940&loc=SL4569616-111683 false2Net income (loss) from continuing operation26true 4us-gaap_AssetsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Assets:27false 5us-gaap_Assetsus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse313778000313778USD$falsetruefalse2falsefalsefalse00falsefalsefalse3truefalsefalse313778000313778USD$falsetruefalse4falsefalsefalse00falsefalsefalse5truefalsefalse231282000231282USD$falsetruefalsexbrli:monetaryItemTypemonetarySum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.18) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 12 -Article 7 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 18 -Article 5 false2Total assets1Total operating and interest expense includes operating costs on commercial property assets for the Investments segment and costs to perform required functions under the management agreement for the Asset Management segment. Depreciation and amortization of $1,256 and $86 and provision for taxes of $4,846 and $3,419 for the six months ended June 30, 2013 and 2012, respectively, are included in the amounts presented above. Depreciation and amortization of $919 and $45 and provision for taxes of $4,441 and $2,107 for the three months ended June 30, 2013 and 2012, respectively, are included in the amounts presented above.2Net income (loss) from continuing operations represents loss before discontinued operations.falseSegment Reporting (Details) (USD $)ThousandsUnKnownUnKnownUnKnowntruefalsefalseSheethttp://www.gramercycapitalcorp.com/role/SegmentReportingDetails527