Reserves For Losses (Details 3) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Cardmember Loans And Related Reserves Evaluated Separately And Collectively For Impairment [Abstract]
Cardmember loans evaluated separately for impairment	$ 699	$ 744
Reserves on cardmember loans evaluated separately for impairment	165	176
Cardmember loans evaluated collectively for impairment	60,280	61,877
Reserves on cardmember loans evaluated collectively for impairment	$ 1,382	$ 1,698