Investment in Partially Owned Entities (Details 3) (Unconsolidated Entities [Member], USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Unconsolidated Entities [Member]
Schedule of Debt Maturities of the Unconsolidated Entities
2012	$ 227,091
2013	173,025
2014	139,152
2015	119,513
2016	33,291
Thereafter	713,879
Unconsolidated third party debt, total	$ 1,405,951	$ 1,402,462

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-Article 9

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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