Reserves For Losses (Details 3) (USD $) In Millions, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Card Member Loans And Related Reserves Evaluated Separately And Collectively For Impairment [Abstract]
Card Member loans evaluated individually for impairment	$ 337	$ 378
Reserves on Card Member loans evaluated individually for impairment	80	84
Card Member loans evaluated collectively for impairment	63,679	66,860
Reserves on Card Member loans evaluated collectively for impairment	$ 1,111	$ 1,177