Card Member Receivables and Loans (Details Textuals) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net volume of Card Member receivables purchased	$ 110,000	$ 111,000
Net volume of Card Member loans purchased	1,900	$ 2,100
Deferred discount revenue on Card Member receivable	26		$ 16
RFC VIII [Member]
Related Party Transaction [Line Items]
Participation Interests In Card Member Receivables Purchased	$ 4,800		$ 2,800