Guarantees and Contingent Liabilities (Details Textual) (USD $)	6 Months Ended	12 Months Ended
	Jun. 30, 2012	Dec. 31, 2011	Mar. 31, 2012	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010
Guarantees and Contingent Liabilities (Textual) [Abstract]
Liability related to the remaining Visa Litigation, carrying amount		$ 65,000,000
Value of airline tickets purchased to deliver at a future date	7,900,000,000
Company held collateral in escrow deposits, letters of credit and indemnities from financial institutions, and liens on various assets	669,000,000
Representation and Warranty Reserve	216,000,000	160,000,000	202,000,000	173,000,000	181,000,000	180,000,000
Increase in representation and warranty reserve primarily due to an increase in the number of loans selected for repurchase review	56,000,000
Unresolved Representation and Warranty Claims	164,000,000	105,000,000
Settlement amount by the Company in exchange for a release of claims	55,000,000
Accrual of potential settlement related to mortgage activities		130,000,000
Amount of deposits falsely overstated by customer	$ 200,000,000