Reserves for Losses (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Changes in the Card Member loans reserve for losses
Balance, January 1			$ 1,261	$ 1,471
Card Member loans - provisions	282	334	532	577
Card Member loans net write-offs - principal			(541)	(613)
Card Member loans net write-offs - interest and fees			(84)	(77)
Card Member loans - other			2	(16)
Balance, June 30	$ 1,170	$ 1,342	$ 1,170	$ 1,342