Investment in Real Estate Joint Ventures Net (Detail) (USD $) In Thousands, unless otherwise specified			12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010 Unconsolidated Joint Ventures
Investments in and Advances to Affiliates [Line Items]
Real estate, net			$ 456,714
Cash			14,995
Other assets			49,717
Total assets			521,426
Mortgages payable			459,922
Notes payable to affiliate			14,824
Other liabilities			20,982
Partners' capital			25,698
Total liabilities and partners' capital			521,426
Our share of unconsolidated debt	1,141,858	1,029,553	246,480
Our share of partners' capital			(10,457)
Our investment in real estate joint ventures			39,816
Our distributions in excess of earnings of real estate joint ventures			(14,060)
Our investment in real estate joint ventures, net			$ 25,756

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