Reportable Operating Segments (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Segment Reporting Information [Line Items]
Non-interest revenues	$ 6,877	$ 8,786	$ 20,648	$ 25,855
Revenue from contracts with customers	5,380	7,051	16,033	20,827
Interest income	2,324	3,080	7,796	8,999
Interest expense	450	877	1,708	2,663
Total revenues net of interest expense	8,751	10,989	26,736	32,191
Net income (loss)	1,073	1,755	1,697	5,066
Total assets	187,259	194,000	187,259	194,000	$ 198,321
Global Consumer Services Group [Member]
Segment Reporting Information [Line Items]
Non-interest revenues	3,517	4,226	10,343	12,331
Revenue from contracts with customers	2,364	3,047	6,893	8,931
Interest income	1,916	2,402	6,298	6,971
Interest expense	242	437	842	1,318
Total revenues net of interest expense	5,191	6,191	15,799	17,984
Net income (loss)	855	991	1,583	2,826
Total assets	81,000	99,000	81,000	99,000
Global Commercial Services [Member]
Segment Reporting Information [Line Items]
Non-interest revenues	2,327	3,070	7,129	9,055
Revenue from contracts with customers	1,969	2,668	5,993	7,874
Interest income	351	485	1,252	1,407
Interest expense	139	262	493	787
Total revenues net of interest expense	2,539	3,293	7,888	9,675
Net income (loss)	220	568	198	1,641
Total assets	40,000	54,000	40,000	54,000
Global Merchant and Network Services [Member]
Segment Reporting Information [Line Items]
Non-interest revenues	1,111	1,471	3,376	4,398
Revenue from contracts with customers	1,053	1,337	3,168	4,017
Interest income	4	6	14	22
Interest expense	(18)	(74)	(60)	(241)
Total revenues net of interest expense	1,133	1,551	3,450	4,661
Net income (loss)	263	523	746	1,658
Total assets	12,000	17,000	12,000	17,000
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Non-interest revenues	(78)	19	(200)	71
Revenue from contracts with customers	(6)	(1)	(21)	5
Interest income	53	187	232	599
Interest expense	87	252	433	799
Total revenues net of interest expense	(112)	(46)	(401)	(129)
Net income (loss)	(265)	(327)	(830)	(1,059)
Total assets	$ 54,000	$ 24,000	$ 54,000	$ 24,000