Investments (Details Textuals 23) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Investments [Abstract]
Carrying value of mortgage loans issued by the Company to real estate joint ventures that the Company has an investment	$ 184	$ 286

For an unclassified balance sheet, amounts due from an entity in which the reporting entity shares joint control with another party or group.

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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