Derivatives and Hedging Activities (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011	Mar. 31, 2011
Fair values, Volume of activity and gain/loss information related to derivative instruments
Derivative asset designated as hedging instrument	$ 532	$ 589	$ 383
Derivative liability designated as hedging instrument	20	174	216
Derivative asset not designated as hedging instrument	1,593	1,808	1,789
Derivative liability not designated as hedging instrument	1,581	1,830	1,802
Netting adjustments, Derivative assets	(1,295)	(1,452)	(1,167)
Netting adjustments, Derivative liabilities	(847)	(978)	(912)
Notional Amount, Total	88,085	74,544	72,888
Derivative Assets, Total	830	945	1,005
Derivative Liabilities, Total	754	1,026	1,106
Designated [Member]
Fair values, Volume of activity and gain/loss information related to derivative instruments
Notional Amount	15,368	15,621	11,313
Nondesignated [Member]
Fair values, Volume of activity and gain/loss information related to derivative instruments
Notional Amount	72,717	58,923	61,575
Interest rate [Member]
Fair values, Volume of activity and gain/loss information related to derivative instruments
Derivative asset designated as hedging instrument	532	589	383
Derivative liability designated as hedging instrument	20	27	41
Derivative asset not designated as hedging instrument	1,190	1,364	1,128
Derivative liability not designated as hedging instrument	1,193	1,371	1,140
Interest rate [Member] | Designated [Member]
Fair values, Volume of activity and gain/loss information related to derivative instruments
Notional Amount	15,368	15,067	10,151
Interest rate [Member] | Nondesignated [Member]
Fair values, Volume of activity and gain/loss information related to derivative instruments
Notional Amount	61,369	48,537	49,941
Foreign exchange [Member]
Fair values, Volume of activity and gain/loss information related to derivative instruments
Derivative liability designated as hedging instrument		147	175
Derivative asset not designated as hedging instrument	94	151	204
Derivative liability not designated as hedging instrument	84	141	193
Foreign exchange [Member] | Designated [Member]
Fair values, Volume of activity and gain/loss information related to derivative instruments
Notional Amount		554	1,162
Foreign exchange [Member] | Nondesignated [Member]
Fair values, Volume of activity and gain/loss information related to derivative instruments
Notional Amount	6,316	5,549	6,494
Energy and commodity [Member]
Fair values, Volume of activity and gain/loss information related to derivative instruments
Derivative asset not designated as hedging instrument	271	253	418
Derivative liability not designated as hedging instrument	267	253	430
Energy and commodity [Member] | Nondesignated [Member]
Fair values, Volume of activity and gain/loss information related to derivative instruments
Notional Amount	1,632	1,610	1,995
Credit [Member]
Fair values, Volume of activity and gain/loss information related to derivative instruments
Derivative asset not designated as hedging instrument	35	37	36
Derivative liability not designated as hedging instrument	34	62	36
Credit [Member] | Nondesignated [Member]
Fair values, Volume of activity and gain/loss information related to derivative instruments
Notional Amount	3,382	3,210	3,127
Equity [Member]
Fair values, Volume of activity and gain/loss information related to derivative instruments
Derivative asset not designated as hedging instrument	3	3	3
Derivative liability not designated as hedging instrument	3	3	3
Equity [Member] | Nondesignated [Member]
Fair values, Volume of activity and gain/loss information related to derivative instruments
Notional Amount	$ 18	$ 17	$ 18