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Joint Ventures (Details Textual) | 1 Months Ended | 2 Months Ended | 12 Months Ended |
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Oct. 20, 2015 | Feb. 19, 2016 USD ($) | Dec. 31, 2015 Communities | Dec. 31, 2015 Communities | Dec. 31, 2015 Communities | Dec. 31, 2015 USD ($) Communities | Dec. 31, 2014 USD ($) | Dec. 31, 2013 USD ($) | Dec. 31, 2015 | Dec. 31, 2015 USD ($) | Dec. 31, 2015 Apartment_Homes
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |
Casualty-related (recoveries)/charges, net |  |  |  |  |  | $ (2,335,000) | $ (541,000) | $ 12,253,000 |  |  |
Joint Ventures |  |  |  |  |  |  |  |  |  |  |
Real Estate Investment Property, Net |  |  |  |  |  |  | 5,770,855,000 |  |  | $ 6,407,555,000 |
Joint venture, number of homes in communities | Apartment_Homes |  |  |  |  |  |  |  |  |  |  | 6,696
Unamortized discount |  |  |  |  |  |  | 6,700,000 |  |  | 10,000,000 |
First installment of payable incurred in partial consideration for acquisition of ownership interest in joint venture |  |  |  |  |  |  |  |  |  | 244,111,000 |
Second installment of payable incurred in partial consideration for acquisition of ownership interest in joint venture |  |  |  |  |  |  |  |  |  | 275,526,000 |
Interest expense incurred during period |  |  |  |  |  | 121,875,000 | 130,454,000 | 126,083,000 |  |  |
Investment in and advances to unconsolidated joint ventures, net |  |  |  |  |  |  | 718,226,000 |  |  | 938,906,000 |
Weighted Average Interest Rate |  |  |  |  | 3.74% |  |  |  |  |  |
Payments to acquire equity method investments |  |  |  |  |  | 217,642,000 | 222,930,000 | 43,291,000 |  |  |
Document Period End Date |  |  | Dec. 31, 2015 |  |  |  |  |  |  |  |
Deferred gains on the sale of depreciable property |  |  |  |  |  |  | 24,700,000 |  |  | 6,800,000 |
Communities Sold |  |  |  | 12 | 9 |  |  |  |  |  |
Proceeds from Sale of Property, Plant, and Equipment |  |  |  |  |  | 408,700,000 | 328,400,000 | 81,100,000 |  |  |
Gain (Loss) on Disposition of Property Plant Equipment |  |  |  |  |  | 138,600,000 |  |  |  |  |
Management fees for our involvement in the joint ventures |  |  |  |  |  | 11,300,000 | 11,300,000 | 11,200,000 |  |  |
Real Estate Owned Gross |  |  |  |  |  |  | 8,383,259,000 |  |  | 9,190,276,000 |
Secured debt, net |  |  |  |  |  |  | 1,354,321,000 |  |  | $ 1,376,945,000 |
SEC Schedule III, Real Estate, Cost of Real Estate Sold |  |  |  |  |  | $ 301,920,000 | 269,681,000 | 70,687,000 |  |  |
Number of Real Estate Properties |  |  | 133 | 133 | 133 | 133 |  |  | 2 |  |
Number of extension options on loan | 2 |  |  |  |  |  |  |  |  |  |
Extension period of option on loan | 6 months |  |  |  |  |  |  |  |  |  |
Number of markets operating within |  |  |  |  |  |  |  |  |  | 18 |
Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |  |
Joint Ventures |  |  |  |  |  |  |  |  |  |  |
Proceeds from Sale of Property, Plant, and Equipment |  | $ 13,500,000 |  |  |  |  |  |  |  |  |
Gain (Loss) on Disposition of Property Plant Equipment |  | $ 2,100,000 |  |  |  |  |  |  |  |  |
Land |  |  |  |  |  |  |  |  |  |  |
Joint Ventures |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment, Additions |  |  |  |  |  | $ 77,800,000 |  |  |  |  |
717 Olympic [Member] |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |
Casualty-related (recoveries)/charges, net |  |  |  |  |  | 2,500,000 |  |  |  |  |
Unconsolidated Joint Venture Other MetLife [Member] |  |  |  |  |  |  |  |  |  |  |
Joint Ventures |  |  |  |  |  |  |  |  |  |  |
Investment in and advances to unconsolidated joint ventures, net |  |  |  |  |  |  | 197,646,000 |  |  | $ 407,102,000 |
Unconsolidated Joint Venture Vitruvian Park [Member] |  |  |  |  |  |  |  |  |  |  |
Joint Ventures |  |  |  |  |  |  |  |  |  |  |
Investment in and advances to unconsolidated joint ventures, net |  |  |  |  |  |  | 80,302,000 |  |  | 73,469,000 |
MetLife I |  |  |  |  |  |  |  |  |  |  |
Joint Ventures |  |  |  |  |  |  |  |  |  |  |
Investment in and advances to unconsolidated joint ventures, net |  |  |  |  |  |  | 13,306,000 |  |  | 15,894,000 |
MetLife II |  |  |  |  |  |  |  |  |  |  |
Joint Ventures |  |  |  |  |  |  |  |  |  |  |
Investment in and advances to unconsolidated joint ventures, net |  |  |  |  |  |  | 431,277,000 |  |  | 425,230,000 |
KFH |  |  |  |  |  |  |  |  |  |  |
Joint Ventures |  |  |  |  |  |  |  |  |  |  |
Investment in and advances to unconsolidated joint ventures, net |  |  |  |  |  |  | 21,596,000 |  |  | 17,211,000 |
Texas JV |  |  |  |  |  |  |  |  |  |  |
Joint Ventures |  |  |  |  |  |  |  |  |  |  |
Investment in and advances to unconsolidated joint ventures, net |  |  |  |  |  |  | $ (25,901,000) |  |  | 0 |
Deferred gains on the sale of depreciable property |  |  |  |  |  |  |  |  |  | 24,200,000 |
Communities Sold |  |  |  |  | 8 |  |  |  |  |  |
Proceeds from Sale of Property, Plant, and Equipment |  |  |  |  |  | 44,200,000 |  |  |  |  |
Fee Income from the Sale of Real Estate |  |  |  |  |  | 10,000,000 |  |  |  |  |
Gain (Loss) on Disposition of Property Plant Equipment |  |  |  |  |  | 59,400,000 |  |  |  |  |
Unconsolidated Joint Venture Wolff [Member] |  |  |  |  |  |  |  |  |  |  |
Joint Ventures |  |  |  |  |  |  |  |  |  |  |
Initial investment in equity method investment |  |  |  |  |  |  |  |  |  | 136,300,000 |
Equity method investment, ownership percent |  |  |  |  |  |  |  |  | 4800.00% |  |
Total Fixed Price Option Sales Price |  |  |  |  |  | 597,400,000 |  |  |  |  |
Number of markets operating within |  |  |  |  |  |  |  |  | 3 |  |
Preferred Return Interest Rate |  |  |  |  | 650.00% |  |  |  |  |  |
Community Threshold, Percent Occupancy Threshold |  |  |  |  | 8000.00% |  |  |  |  |  |
Community Threshold, Period Above Occupancy Threshold |  |  | 90 days |  |  |  |  |  |  |  |
Fixed Price Option Period |  |  | 1 year |  |  |  |  |  |  |  |
Land |  |  |  |  |  |  |  |  |  |  |
Joint Ventures |  |  |  |  |  |  |  |  |  |  |
Gain (Loss) on Disposition of Property Plant Equipment |  |  |  |  |  | 1,100,000 |  |  |  |  |
Land | Unconsolidated Joint Venture Other MetLife [Member] |  |  |  |  |  |  |  |  |  |  |
Joint Ventures |  |  |  |  |  |  |  |  |  |  |
Number of Real Estate Properties |  |  |  |  |  |  |  |  | 1 |  |
Land | MetLife I |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |
Number of apartments of development community |  |  |  |  |  |  |  |  | 0 |  |
Operating Community [Member] |  |  |  |  |  |  |  |  |  |  |
Joint Ventures |  |  |  |  |  |  |  |  |  |  |
Communities Sold |  |  |  |  | 1 |  |  |  |  |  |
Gain (Loss) on Disposition of Property Plant Equipment |  |  |  |  |  | 142,500,000 |  |  |  |  |
Operating Community [Member] | Unconsolidated Joint Venture Other MetLife [Member] |  |  |  |  |  |  |  |  |  |  |
Joint Ventures |  |  |  |  |  |  |  |  |  |  |
Number of Units in Real Estate Property |  |  |  |  |  |  |  |  | 1,437 |  |
Equity method investment, ownership percent |  |  |  |  |  |  | 50.60% |  | 50.60% |  |
Investment in and advances to unconsolidated joint ventures, net |  |  |  |  |  |  | $ 134,939,000 |  |  | 171,659,000 |
Number of Real Estate Properties |  |  |  |  |  |  |  |  | 1 |  |
Operating Community [Member] | Unconsolidated Joint Venture Vitruvian Park [Member] |  |  |  |  |  |  |  |  |  |  |
Joint Ventures |  |  |  |  |  |  |  |  |  |  |
Number of Units in Real Estate Property |  |  |  |  |  |  |  |  | 1,130 |  |
Equity method investment, ownership percent |  |  |  |  |  |  | 50.00% |  | 50.00% |  |
Investment in and advances to unconsolidated joint ventures, net |  |  |  |  |  |  | $ 80,302,000 |  |  | 73,469,000 |
Number of Real Estate Properties |  |  |  |  |  |  |  |  | 3 |  |
Operating Community [Member] | MetLife I |  |  |  |  |  |  |  |  |  |  |
Joint Ventures |  |  |  |  |  |  |  |  |  |  |
Number of Units in Real Estate Property |  |  |  |  |  |  |  |  | 0 |  |
Equity method investment, ownership percent |  |  |  |  |  |  | 15.70% |  | 17.20% |  |
Investment in and advances to unconsolidated joint ventures, net |  |  |  |  |  |  | $ 13,306,000 |  |  | 15,894,000 |
Number of Real Estate Properties |  |  |  |  |  |  |  |  | 4 |  |
Operating Community [Member] | MetLife II |  |  |  |  |  |  |  |  |  |  |
Joint Ventures |  |  |  |  |  |  |  |  |  |  |
Number of Units in Real Estate Property |  |  |  |  |  |  |  |  | 4,642 |  |
Equity method investment, ownership percent |  |  |  |  |  |  | 50.00% |  | 50.00% |  |
Investment in and advances to unconsolidated joint ventures, net |  |  |  |  |  |  | $ 431,277,000 |  |  | 425,230,000 |
Number of Real Estate Properties |  |  |  |  |  |  |  |  | 21 |  |
Operating Community [Member] | KFH |  |  |  |  |  |  |  |  |  |  |
Joint Ventures |  |  |  |  |  |  |  |  |  |  |
Number of Units in Real Estate Property |  |  |  |  |  |  |  |  | 660 |  |
Equity method investment, ownership percent |  |  |  |  |  |  | 30.00% |  | 30.00% |  |
Investment in and advances to unconsolidated joint ventures, net |  |  |  |  |  |  | $ 21,596,000 |  |  | 17,211,000 |
Number of Real Estate Properties |  |  |  |  |  |  |  |  | 3 |  |
Operating Community [Member] | Texas JV |  |  |  |  |  |  |  |  |  |  |
Joint Ventures |  |  |  |  |  |  |  |  |  |  |
Equity method investment, ownership percent |  |  |  |  |  |  | 20.00% |  | 0.00% |  |
Operating Community [Member] | Unconsolidated Joint Venture Wolff [Member] |  |  |  |  |  |  |  |  |  |  |
Joint Ventures |  |  |  |  |  |  |  |  |  |  |
Number of Units in Real Estate Property |  |  |  |  |  |  |  |  | 1,533 |  |
Number of Real Estate Properties |  |  |  |  |  |  |  |  | 2 |  |
Development Community [Member] | Unconsolidated Joint Venture Other MetLife [Member] |  |  |  |  |  |  |  |  |  |  |
Joint Ventures |  |  |  |  |  |  |  |  |  |  |
Number of Real Estate Properties |  |  |  |  |  |  |  |  | 4 |  |
Development Community [Member] | Texas JV |  |  |  |  |  |  |  |  |  |  |
Joint Ventures |  |  |  |  |  |  |  |  |  |  |
Number of Units in Real Estate Property |  |  |  |  |  |  |  |  | 0 |  |
Investment in and advances to unconsolidated joint ventures, net |  |  |  |  |  |  | $ (25,901,000) |  |  | 0 |
Number of Real Estate Properties |  |  |  |  |  |  |  |  | 0 |  |
Development Community [Member] | Participating Loan Investment Steele Creek Denver Colorado [Member] |  |  |  |  |  |  |  |  |  |  |
Joint Ventures |  |  |  |  |  |  |  |  |  |  |
Investment in and advances to unconsolidated joint ventures, net |  |  |  |  |  |  | 62,707,000 |  |  | 90,747,000 |
Income from Participating Loan |  |  |  |  |  | 5,453,000 | 2,350,000 | 156,000 |  |  |
Development Community [Member] | Unconsolidated Joint Venture Wolff [Member] |  |  |  |  |  |  |  |  |  |  |
Joint Ventures |  |  |  |  |  |  |  |  |  |  |
Number of Real Estate Properties |  |  |  |  |  |  |  |  | 5 |  |
Development Community [Member] | Preferred Equity Investment West Coast Development JV [Member] |  |  |  |  |  |  |  |  |  |  |
Joint Ventures |  |  |  |  |  |  |  |  |  |  |
Investment in and advances to unconsolidated joint ventures, net |  |  |  |  |  |  | 0 |  |  | $ 144,696,000 |
Income from Participating Loan |  |  |  |  |  | 3,692,000 | $ 0 | $ 0 |  |  |
Equity Method Investment, Preferred Return |  |  |  |  |  | 5,200,000 |  |  |  |  |
Equity Method Investment, Transaction Expenses |  |  |  |  |  | 1,500,000 |  |  |  |  |
Participating Loan Investment Steele Creek Denver Colorado [Member] |  |  |  |  |  |  |  |  |  |  |
Joint Ventures |  |  |  |  |  |  |  |  |  |  |
Number of Real Estate Properties |  |  |  |  |  |  |  |  | 1 |  |
13th & Market [Member] |  |  |  |  |  |  |  |  |  |  |
Joint Ventures |  |  |  |  |  |  |  |  |  |  |
Equity method investment, ownership percent |  |  |  |  |  |  |  |  | 49.00% |  |
Proceeds from Sale of Property, Plant, and Equipment |  |  |  |  |  | 54,200,000 |  |  |  |  |
Gain (Loss) on Disposition of Property Plant Equipment |  |  |  |  |  | 7,200,000 |  |  |  |  |
3033 Wilshire |  |  |  |  |  |  |  |  |  |  |
Joint Ventures |  |  |  |  |  |  |  |  |  |  |
Equity method investment, ownership percent |  |  |  |  |  |  |  |  | 50.00% |  |
Proceeds from Sale of Property, Plant, and Equipment |  |  |  |  |  | 8,300,000 |  |  |  |  |
Gain (Loss) on Disposition of Property Plant Equipment |  |  |  |  |  | $ 2,200,000 |  |  |  |  |

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