Goodwill and Other Intangible Assets - Other Intangible Assets (Details 6) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Intangible Assets By Major Class [Line Items]
Servicing Asset at Fair Value, Changes in Fair Value Resulting From Changes in Market Interest Rates	$ (589)	$ (5,392)	$ (2,224)
Increase (Decrease) In Other Intangible Assets	(972)
Amortization of intangibles	957	848	936
Components of credit card relationships, core deposits and other intangible assets [Abstract]
Components of credit card relationships, core deposits and other intangible assets , Net Carrying Value	2,235	3,207	4,039
Indefinite-Lived Intangible Assets (Excluding Goodwill)	600
Purchased Credit Card Relationships [Member]
Intangible Assets By Major Class [Line Items]
Amortization of intangibles	309	295	355
Components of credit card relationships, core deposits and other intangible assets [Abstract]
Components of credit card relationships, core deposits and other intangible assets , Gross amount	3,775	3,826
Components of credit card relationships, core deposits and other intangible assets , Accumulated amortization	3,480	3,224
Components of credit card relationships, core deposits and other intangible assets , Net Carrying Value	295	602	897
Other credit card- related intangibles [Member]
Intangible Assets By Major Class [Line Items]
Amortization of intangibles	265	106	111
Components of credit card relationships, core deposits and other intangible assets [Abstract]
Components of credit card relationships, core deposits and other intangible assets , Gross amount	850	844
Components of credit card relationships, core deposits and other intangible assets , Accumulated amortization	621	356
Components of credit card relationships, core deposits and other intangible assets , Net Carrying Value	229	488	593
Core Deposit Intangibles [Member]
Intangible Assets By Major Class [Line Items]
Amortization of intangibles	239	285	328
Components of credit card relationships, core deposits and other intangible assets [Abstract]
Components of credit card relationships, core deposits and other intangible assets , Gross amount	4,133	4,133
Components of credit card relationships, core deposits and other intangible assets , Accumulated amortization	3,778	3,539
Components of credit card relationships, core deposits and other intangible assets , Net Carrying Value	355	594	879
Other intangibles [Member]
Components of credit card relationships, core deposits and other intangible assets [Abstract]
Components of credit card relationships, core deposits and other intangible assets , Gross amount	2,390	2,467
Components of credit card relationships, core deposits and other intangible assets , Accumulated amortization	1,034	944
Components of credit card relationships, core deposits and other intangible assets , Net Carrying Value	1,356	1,523
Impairment of Intangible Assets [Member]
Intangible Assets By Major Class [Line Items]
Amortization of intangibles	$ 214