Reportable Operating Segments (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Segment Reporting Information [Line Items]
Non-interest revenues	$ 5,791	$ 8,764	$ 13,771	$ 17,069
Revenue from contracts with customers	4,357	7,080	10,653	13,776
Interest income	2,426	2,965	5,472	5,919
Interest expense	542	891	1,258	1,786
Total revenues net of interest expense	7,675	10,838	17,985	21,202
Net income (loss)	257	1,761	624	3,311
Total assets	188,608	198,000	188,608	198,000	$ 198,321
Global Consumer Services Group [Member]
Segment Reporting Information [Line Items]
Non-interest revenues	2,932	4,193	6,826	8,105
Revenue from contracts with customers	1,836	3,060	4,530	5,884
Interest income	1,971	2,297	4,382	4,569
Interest expense	272	446	600	881
Total revenues net of interest expense	4,631	6,044	10,608	11,793
Net income (loss)	527	881	728	1,835
Total assets	80,000	102,000	80,000	102,000
Global Commercial Services [Member]
Segment Reporting Information [Line Items]
Non-interest revenues	2,014	3,059	4,802	5,985
Revenue from contracts with customers	1,652	2,665	4,024	5,206
Interest income	402	468	901	922
Interest expense	154	269	354	525
Total revenues net of interest expense	2,262	3,258	5,349	6,382
Net income (loss)	(60)	561	(22)	1,073
Total assets	38,000	55,000	38,000	55,000
Global Merchant and Network Services [Member]
Segment Reporting Information [Line Items]
Non-interest revenues	919	1,478	2,265	2,927
Revenue from contracts with customers	875	1,355	2,115	2,680
Interest income	4	7	10	16
Interest expense	(6)	(87)	(42)	(167)
Total revenues net of interest expense	929	1,572	2,317	3,110
Net income (loss)	66	564	483	1,135
Total assets	12,000	22,000	12,000	22,000
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Non-interest revenues	(74)	34	(122)	52
Revenue from contracts with customers	(6)	0	(16)	6
Interest income	49	193	179	412
Interest expense	122	263	346	547
Total revenues net of interest expense	(147)	(36)	(289)	(83)
Net income (loss)	(276)	(245)	(565)	(732)
Total assets	$ 59,000	$ 19,000	$ 59,000	$ 19,000