Goodwill and Other Intangible Assets - Other Intangible Assets (Details 6) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Dec. 31, 2012
Intangible Assets By Major Class [Line Items]
Increase (Decrease) In Other Intangible Assets	$ (153)
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	2,082	2,235
Indefinite-Lived Intangible Assets (Excluding Goodwill)	600
Purchased Credit Card Relationships [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	3,509	3,775
Components of credit card relationships, core deposits and other intangible assets , Accumulated amortization	3,267	3,480
Components of credit card relationships, core deposits and other intangible assets , Net Carrying Value	242	295
Other credit card- related 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	538	850
Components of credit card relationships, core deposits and other intangible assets , Accumulated amortization	325	621
Components of credit card relationships, core deposits and other intangible assets , Net Carrying Value	213	229
Core Deposit 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	4,133	4,133
Components of credit card relationships, core deposits and other intangible assets , Accumulated amortization	3,828	3,778
Components of credit card relationships, core deposits and other intangible assets , Net Carrying Value	305	355
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	2,388	2,390
Components of credit card relationships, core deposits and other intangible assets , Accumulated amortization	1,066	1,034
Components of credit card relationships, core deposits and other intangible assets , Net Carrying Value	$ 1,322	$ 1,356