Accounts Receivable and Loans (Details 4) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Impaired loans and receivables
Loans over 90 days past due and accruing interest	$ 216	$ 218	$ 221
Non-accrual loans	150	241	298
Loans and receivables modified as a Troubled Debt Restructuring in Program	199	334	406
Loans and receivables modified as Troubled Debt Restructuring Out of Program	113
Total impaired loans and receivables	678	793	925
Unpaid principal balance	632	750	886
Related allowance for Troubled Debt Restructurings	73	102	116
Average balance of impaired loans	760	859	1,096
Interest income recognized	73	65	62
Accounts Receivable and Loans (Textuals) [Abstract]
Total loans and receivables modified as a TDR, non-accrual	18	34	43
Total loans and receivables modified as a TDR, past due 90 days and still accruing	20	26	29
Out of Program TDR accounts that completed modification programs	84
Out of Program TDR accounts not in compliance with modification programs	29
U S Card Services [Member] | Card Member Loans [Member]
Impaired loans and receivables
Loans over 90 days past due and accruing interest	164	161	167
Non-accrual loans	150	241	294
Loans and receivables modified as a Troubled Debt Restructuring in Program	172	286	351
Loans and receivables modified as Troubled Debt Restructuring Out of Program	107
Total impaired loans and receivables	593	688	812
Unpaid principal balance	548	646	775
Related allowance for Troubled Debt Restructurings	53	67	78
Average balance of impaired loans	673	750	948
Interest income recognized	59	49	46
U S Card Services [Member] | Card Member Receivables [Member]
Impaired loans and receivables
Loans over 90 days past due and accruing interest	0	0	0
Non-accrual loans	0	0	0
Loans and receivables modified as a Troubled Debt Restructuring in Program	27	48	50
Loans and receivables modified as Troubled Debt Restructuring Out of Program	6
Total impaired loans and receivables	33	48	50
Unpaid principal balance	33	48	49
Related allowance for Troubled Debt Restructurings	20	35	38
Average balance of impaired loans	33	47	81
Interest income recognized	0	0	0
International Card Services [Member] | Card Member Loans [Member]
Impaired loans and receivables
Loans over 90 days past due and accruing interest	52	57	54
Non-accrual loans	0	0	4
Loans and receivables modified as a Troubled Debt Restructuring in Program	0	0	5
Loans and receivables modified as Troubled Debt Restructuring Out of Program	0
Total impaired loans and receivables	52	57	63
Unpaid principal balance	51	56	62
Related allowance for Troubled Debt Restructurings	0	0	0
Average balance of impaired loans	54	62	67
Interest income recognized	$ 14	$ 16	$ 16