Business Changes and Developments - Other Business Events (Details 2) (USD $) In Millions, unless otherwise specified	12 Months Ended				3 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2012 Global settlement on servicing and origination of mortgages [Member]	Mar. 31, 2012 Washington Mutual, Inc. bankruptcy plan confirmation [Member]	Apr. 05, 2012 Settlement of Litigation, Cash Payments [Member] Global settlement on servicing and origination of mortgages [Member] Mortgage Foreclosure Investigations and Litigation [Member]	Apr. 05, 2012 Settlement of Litigation, Refinancing Relief Provided to Certain Borrowers [Member] Global settlement on servicing and origination of mortgages [Member] Mortgage Foreclosure Investigations and Litigation [Member]	Apr. 05, 2012 Settlement of Litigation, Additional Relief Provided to Certain Borrowers [Member] Global settlement on servicing and origination of mortgages [Member] Mortgage Foreclosure Investigations and Litigation [Member]
Other Business Events Disclousre [Line Items]
Loss Contingency, Settlement Agreement, Consideration						$ 1,100.0	$ 500.0	$ 3,700.0
Refinancing and Borrower Relief Target To Be Met Within Two Years				75.00%
Refinancing and Borrower Relief Target To Be Met Within Three Years				100.00%
Noninterest Income, Other	$ 4,258	$ 2,605	$ 2,044		$ 1,100