Reserves For Losses (Details Textuals) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]
Cardmember receivables reserves for losses - other	$ 80	$ 41
Cardmember loans reserves for losses - other	78	53
Allowance for Cardmember Receivables and Reserves, Recoveries of Bad Debts	200	193
Allowance for Cardmember Loans, Recoveries of Bad Debts	230	258
Unauthorized Transactions [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Cardmember receivables reserves for losses - other	(80)	(63)
Cardmember loans reserves for losses - other	(62)	(53)
Foreign Currency Translation Adjustments [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Cardmember receivables reserves for losses - other	(6)	(2)
Cardmember loans reserves for losses - other	(11)	(1)
Cardmember Bankruptcy Reserves [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Cardmember receivables reserves for losses - other	0	18
Cardmember loans reserves for losses - other	0	4
Other Items [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Cardmember receivables reserves for losses - other	6	6
Cardmember loans reserves for losses - other	$ (5)	$ (3)