Reportable Operating Segments and Geographic Operations (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Segment Reporting Information [Line Items]
Non-interest revenues	$ 7,341	$ 7,043	$ 14,203	$ 13,681
Interest income	1,759	1,694	3,535	3,456
Interest expense	443	492	882	1,011
Total revenues, net of interest expense	8,657	8,245	16,856	16,126
Net income	1,529	1,405	2,961	2,685
U S Card Services [Member]
Segment Reporting Information [Line Items]
Non-interest revenues	3,222	3,063	6,239	5,941
Interest income	1,408	1,354	2,831	2,740
Interest expense	153	178	303	360
Total revenues, net of interest expense	4,477	4,239	8,767	8,321
Net income	770	743	1,646	1,547
International Card Services [Member]
Segment Reporting Information [Line Items]
Non-interest revenues	1,208	1,130	2,365	2,254
Interest income	275	259	552	549
Interest expense	92	90	174	187
Total revenues, net of interest expense	1,391	1,299	2,743	2,616
Net income	77	208	236	386
Global Commercial Services [Member]
Segment Reporting Information [Line Items]
Non-interest revenues	1,332	1,290	2,581	2,510
Interest income	3	3	7	6
Interest expense	66	62	125	122
Total revenues, net of interest expense	1,269	1,231	2,463	2,394
Net income	561	226	745	417
Global Network And Merchant Services [Member]
Segment Reporting Information [Line Items]
Non-interest revenues	1,366	1,313	2,659	2,547
Interest income	11	8	21	15
Interest expense	(78)	(63)	(140)	(125)
Total revenues, net of interest expense	1,455	1,384	2,820	2,687
Net income	373	412	816	785
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Non-interest revenues	213	247	359	429
Interest income	62	70	124	146
Interest expense	210	225	420	467
Total revenues, net of interest expense	65	92	63	108
Net income	$ (252)	$ (184)	$ (482)	$ (450)