Reportable Operating Segments and Geographic Operations (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Segment Reporting Information [Line Items]
Non-interest revenues		$ 8,305	$ 7,877
Revenue from contracts with customers	[1]	6,697	6,387
Interest income		2,954	2,462
Interest expense		895	621
Total revenues, net of interest expense		10,364	9,718
Net income		1,550	1,634
Total assets		197,193	180,000	$ 188,602
Global Consumer Services Group [Member]
Segment Reporting Information [Line Items]
Non-interest revenues		3,741	3,491
Revenue from contracts with customers	[1]	2,578	2,438
Interest income		2,272	1,949
Interest expense		459	327
Total revenues, net of interest expense		5,554	5,113
Net income		821	826
Total assets		98,500	91,000
Global Commercial Services [Member]
Segment Reporting Information [Line Items]
Non-interest revenues		3,020	2,838
Revenue from contracts with customers	[1]	2,607	2,454
Interest income		454	377
Interest expense		241	171
Total revenues, net of interest expense		3,233	3,044
Net income		586	546
Total assets		54,000	51,000
Global Merchant and Network Services [Member]
Segment Reporting Information [Line Items]
Non-interest revenues		1,525	1,532
Revenue from contracts with customers	[1]	1,503	1,491
Interest income		9	9
Interest expense		(93)	(59)
Total revenues, net of interest expense		1,627	1,600
Net income		631	516
Total assets		22,100	20,000
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Non-interest revenues		19	16
Revenue from contracts with customers	[1]	9	4
Interest income		219	127
Interest expense		288	182
Total revenues, net of interest expense		(50)	(39)
Net income		(488)	(254)
Total assets		$ 22,400	$ 18,000

[1] Includes discount revenue, certain other fees and commissions and other revenues from customers