Details of Certain Consolidated Statements of Income Lines (Details) (USD $) In Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Component of Other Income, Nonoperating [Line Items]
Total other commissions and fees	$ 604	$ 515	$ 1,717	$ 1,512
Foreign currency conversion revenue [Member]
Component of Other Income, Nonoperating [Line Items]
Total other commissions and fees	225	221	651	614
Delinquency fees [Member]
Component of Other Income, Nonoperating [Line Items]
Total other commissions and fees	155	151	439	463
Service fees [Member]
Component of Other Income, Nonoperating [Line Items]
Total other commissions and fees	89	85	266	247
Other Commissions And Fees [Member]
Component of Other Income, Nonoperating [Line Items]
Total other commissions and fees	$ 135	$ 58	$ 361	$ 188