Asset Quality (Summary of TDRs) (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012		Dec. 31, 2011
Troubled debt restructurings (TDRs)	$ 2,319		$ 2,203
Nonperforming [Member]
Troubled debt restructurings (TDRs)	1,189		1,141
Accruing [Member]
Troubled debt restructurings (TDRs)	878	[1]	771	[1]
Credit Card [Member]
Troubled debt restructurings (TDRs)	252	[2]	291	[2]
Total commercial lending [Member]
Troubled debt restructurings (TDRs)	483		405
Total consumer lending [Member]
Troubled debt restructurings (TDRs)	$ 1,836		$ 1,798

[1] Accruing loans have demonstrated a period of at least six months of performance under the restructured terms and are excluded from nonperforming loans.

[2] Includes credit cards and certain small business and consumer credit agreements whose terms have been restructured and are TDRs. However, since our policy is to exempt these loans from being placed on nonaccrual status as permitted by regulatory guidance as generally these loans are directly charged off in the period that they become 180 days past due, these loans are excluded from nonperforming loans.