Details of Certain Consolidated Statements of Income Lines (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Details Of Certain Statements Of Income Lines Details [Abstract]
Foreign currency conversion revenue	$ 223	$ 220	$ 655	$ 643
Delinquency fees	172	156	503	476
Service fees	97	81	273	263
Other commissions and fees	118	124	357	357
Total other commissions and fees	$ 610	$ 581	$ 1,788	$ 1,739