Equity Investment in Real Estate and the Managed REITs (Details 3) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Managed REITs
Equity Method Investment Summarized Financial Information
Assets	$ 8,052,546	$ 9,184,111
Liabilities	(3,959,756)	(4,896,116)
Reedemable noncontrolling interest	(21,747)	(21,306)
Noncontrolling interests	(170,140)	(330,873)
Partners'/stockholders' equity	3,900,903	3,935,816
Combined Equity Investments
Equity Method Investment Summarized Financial Information
Assets	1,286,294	1,026,124
Liabilities	(799,422)	(706,244)
Reedemable noncontrolling interest	(21,747)	(21,306)
Partners'/stockholders' equity	$ 465,125	$ 298,574

The amount of assets reported by an equity method investment of the entity.

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Reference 8: http://www.xbrl.org/2003/role/presentationRef

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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+ Details

- Definition

Amount of equity, excluding noncontrolling interest, attributable to the equity method investment of the entity.

+ References+ Details

- Definition

The amount of liabilities reported by an equity method investment of the entity.

+ References

+ Details

- Definition

Amount of equity attributable to noncontrolling interests of an equity method investment of the entity.

+ References

+ Details