Card Member Receivables and Loans (Details Textuals) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net volume of Card Member receivables purchased	$ 215,000	$ 220,000	$ 213,000
Net volume of Card Member loans purchased	4,000	4,000	$ 4,000
Deferred discount revenue on Card Member receivable	27	22
RFC VIII [Member]
Related Party Transaction [Line Items]
Participation Interests In Card Member Receivables Purchased	$ 4,000	$ 4,100