Summary of Significant Accounting Policies (Other Assets) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Other Assets
Prepaid Ground Rent	$ 7,615	$ 7,704
Prepaid Real Estate Taxes	7,983	7,648
Rent inducements, net	7,572	6,262
Cash surrender value of life insurance	9,261	8,128
Restricted cash	2,528	4,029
Marketable securities	2,366	2,614
Prepaid insurance	2,589	2,432
Furniture, fixtures and equipment	634	1,613
Deposits on future settlements	3,884	2,035
Others	8,726	12,232
Total	$ 53,158	$ 54,697

Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

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