Investment in Unconsolidated Ventures (Details) (USD $) In Thousands	Sep. 30, 2011	Dec. 31, 2010
Financial position of the Real Estate Ventures
Company's share of equity (Company's basis)	$ 84,219	$ 84,372
Unconsolidated real estate ventures [Member]
Financial position of the Real Estate Ventures
Net property	723,108	804,705
Other Assets	127,863	105,576
Other Liabilities	48,320	44,509
Debt	680,505	748,387
Equity	122,146	117,385
Company's share of equity (Company's basis)	$ 84,219	$ 84,372

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