Derivatives, Net Gains (Losses) in Income Related to Derivatives Not Designated as Hedging Instruments (Details) (Not Designated as Hedging Instrument [Member], USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Net Gains Losses Recognized In Income Statement Related To Derivatives Not Designated As Hedging Instruments [Abstract]
Net gains recognized related to derivatives not designated as hedging instruments	$ 1,656	$ 2,142	$ 4,796	$ 4,368
Customer accommodation trading and other free standing derivatives [Member]
Net Gains Losses Recognized In Income Statement Related To Derivatives Not Designated As Hedging Instruments [Abstract]
Gain (Loss) on Derivative Instruments	3,059	1,736	7,068	4,113
Free standing derivatives (economic hedges) [Member]
Net Gains Losses Recognized In Income Statement Related To Derivatives Not Designated As Hedging Instruments [Abstract]
Gain (Loss) on Derivative Instruments	(1,403)	406	(2,272)	255
Foreign Exchange Contract [Member] | Customer accommodation trading and other free standing derivatives [Member]
Net Gains Losses Recognized In Income Statement Related To Derivatives Not Designated As Hedging Instruments [Abstract]
Gain (Loss) on Derivative Instruments	131	219	380	526
Foreign Exchange Contract [Member] | Free standing derivatives (economic hedges) [Member]
Net Gains Losses Recognized In Income Statement Related To Derivatives Not Designated As Hedging Instruments [Abstract]
Gain (Loss) on Derivative Instruments	(37)	267	(38)	(102)
Equity Contract [Member] | Customer accommodation trading and other free standing derivatives [Member]
Net Gains Losses Recognized In Income Statement Related To Derivatives Not Designated As Hedging Instruments [Abstract]
Gain (Loss) on Derivative Instruments	99	378	20	855
Equity Contract [Member] | Free standing derivatives (economic hedges) [Member]
Net Gains Losses Recognized In Income Statement Related To Derivatives Not Designated As Hedging Instruments [Abstract]
Gain (Loss) on Derivative Instruments	0	0	1	(5)
Commodity Contract [Member] | Customer accommodation trading and other free standing derivatives [Member]
Net Gains Losses Recognized In Income Statement Related To Derivatives Not Designated As Hedging Instruments [Abstract]
Gain (Loss) on Derivative Instruments	(72)	(25)	(116)	76
Other Contract [Member] | Customer accommodation trading and other free standing derivatives [Member]
Net Gains Losses Recognized In Income Statement Related To Derivatives Not Designated As Hedging Instruments [Abstract]
Gain (Loss) on Derivative Instruments	0	(4)	0	(5)
Credit Contract [Member] | Customer accommodation trading and other free standing derivatives [Member]
Net Gains Losses Recognized In Income Statement Related To Derivatives Not Designated As Hedging Instruments [Abstract]
Gain (Loss) on Derivative Instruments	(29)	(382)	(18)	(338)
Credit Contract [Member] | Free standing derivatives (economic hedges) [Member]
Net Gains Losses Recognized In Income Statement Related To Derivatives Not Designated As Hedging Instruments [Abstract]
Gain (Loss) on Derivative Instruments	(3)	(5)	(13)	(13)
Interest Rate Contracts Recognized In Noninterest Income Other [Member] | Customer accommodation trading and other free standing derivatives [Member]
Net Gains Losses Recognized In Income Statement Related To Derivatives Not Designated As Hedging Instruments [Abstract]
Gain (Loss) on Derivative Instruments	136	(95)	466	195
Interest Rate Contracts Recognized In Noninterest Income Other [Member] | Free standing derivatives (economic hedges) [Member]
Net Gains Losses Recognized In Income Statement Related To Derivatives Not Designated As Hedging Instruments [Abstract]
Gain (Loss) on Derivative Instruments	(7)	(133)	(40)	(153)
Interest Rate Contracts Recognized In Noninterest Income Mortgage Banking [Member] | Customer accommodation trading and other free standing derivatives [Member]
Net Gains Losses Recognized In Income Statement Related To Derivatives Not Designated As Hedging Instruments [Abstract]
Gain (Loss) on Derivative Instruments	2,794	1,645	6,336	2,804
Interest Rate Contracts Recognized In Noninterest Income Mortgage Banking [Member] | Free standing derivatives (economic hedges) [Member]
Net Gains Losses Recognized In Income Statement Related To Derivatives Not Designated As Hedging Instruments [Abstract]
Gain (Loss) on Derivative Instruments	$ (1,356)	$ 277	$ (2,182)	$ 528