Fair Value Measurements (Details Textual) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010
Fair Value Measurements (Textual) [Abstract]
Level 3 assets as a percentage of total asset measured at fair value	4.00%
Percentage of level 3 assets that were priced using non-binding broker quotes	95.00%
Total realized/unrealized losses included in net income on liabilities still outstanding	$ 3	$ 213

Fair value measurement with unobservable inputs reconciliation recurring basis liability gain (loss) included in earnings on liabilities still outstanding.

No definition available.

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