Derivatives and Hedging Activities (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Fair values, Volume of activity and gain/loss information related to derivative instruments
Derivative asset designated as hedging instrument	$ 589	$ 458
Derivative liability designated as hedging instrument	174	257
Derivative asset not designated as hedging instrument	1,808	1,846
Derivative liability not designated as hedging instrument	1,830	1,850
Netting adjustments, Derivative assets	(1,452)	(1,298)
Netting adjustments, Derivative liabilities	(978)	(965)
Notional Amount, Total	74,544	71,191
Derivative Assets, Total	945	1,006
Derivative Liabilities, Total	1,026	1,142
Designated [Member]
Fair values, Volume of activity and gain/loss information related to derivative instruments
Notional Amount	15,621	11,679
Nondesignated [Member]
Fair values, Volume of activity and gain/loss information related to derivative instruments
Notional Amount	58,923	59,512
Interest rate [Member]
Fair values, Volume of activity and gain/loss information related to derivative instruments
Derivative asset designated as hedging instrument	589	458
Derivative liability designated as hedging instrument	27	17
Derivative asset not designated as hedging instrument	1,364	1,308
Derivative liability not designated as hedging instrument	1,371	1,319
Interest rate [Member] | Designated [Member]
Fair values, Volume of activity and gain/loss information related to derivative instruments
Notional Amount	15,067	10,586
Interest rate [Member] | Nondesignated [Member]
Fair values, Volume of activity and gain/loss information related to derivative instruments
Notional Amount	48,537	48,344
Foreign exchange [Member]
Fair values, Volume of activity and gain/loss information related to derivative instruments
Derivative asset designated as hedging instrument	0	0
Derivative liability designated as hedging instrument	147	240
Derivative asset not designated as hedging instrument	151	180
Derivative liability not designated as hedging instrument	141	164
Foreign exchange [Member] | Designated [Member]
Fair values, Volume of activity and gain/loss information related to derivative instruments
Notional Amount	554	1,093
Foreign exchange [Member] | Nondesignated [Member]
Fair values, Volume of activity and gain/loss information related to derivative instruments
Notional Amount	5,549	5,946
Energy and commodity [Member]
Fair values, Volume of activity and gain/loss information related to derivative instruments
Derivative asset not designated as hedging instrument	253	318
Derivative liability not designated as hedging instrument	253	335
Energy and commodity [Member] | Nondesignated [Member]
Fair values, Volume of activity and gain/loss information related to derivative instruments
Notional Amount	1,610	1,827
Credit [Member]
Fair values, Volume of activity and gain/loss information related to derivative instruments
Derivative asset not designated as hedging instrument	37	39
Derivative liability not designated as hedging instrument	62	31
Credit [Member] | Nondesignated [Member]
Fair values, Volume of activity and gain/loss information related to derivative instruments
Notional Amount	3,210	3,375
Equity [Member]
Fair values, Volume of activity and gain/loss information related to derivative instruments
Derivative asset not designated as hedging instrument	3	1
Derivative liability not designated as hedging instrument	3	1
Equity [Member] | Nondesignated [Member]
Fair values, Volume of activity and gain/loss information related to derivative instruments
Notional Amount	$ 17	$ 20