Investments (Details Textuals 23) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Investments [Abstract]
Carrying value of mortgage loans issued by the Company to real estate joint ventures that the Company has an investment	$ 286	$ 283

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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+ Details