Reportable Operating Segments (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Segment Reporting Information [Line Items]
Non-interest revenues	$ 8,764	$ 8,173	$ 17,069	$ 16,050
Revenue from contracts with customers	7,080	6,674	13,776	13,061
Interest income	2,965	2,540	5,919	5,002
Interest expense	891	711	1,786	1,332
Total revenues, net of interest expense	10,838	10,002	21,202	19,720
Net income	1,761	1,623	3,311	3,257
Total assets	197,603	185,000	197,603	185,000	$ 188,602
Global Consumer Services Group [Member]
Segment Reporting Information [Line Items]
Non-interest revenues	4,001	3,678	7,742	7,169
Revenue from contracts with customers	2,787	2,596	5,364	5,034
Interest income	2,297	1,994	4,569	3,943
Interest expense	464	370	923	697
Total revenues, net of interest expense	5,834	5,302	11,388	10,415
Net income	738	770	1,559	1,596
Total assets	102,000	96,000	102,000	96,000
Global Commercial Services [Member]
Segment Reporting Information [Line Items]
Non-interest revenues	3,167	2,977	6,187	5,815
Revenue from contracts with customers	2,741	2,581	5,348	5,034
Interest income	468	393	922	770
Interest expense	257	204	498	375
Total revenues, net of interest expense	3,378	3,166	6,611	6,210
Net income	644	564	1,230	1,110
Total assets	55,000	52,000	55,000	52,000
Global Merchant and Network Services [Member]
Segment Reporting Information [Line Items]
Non-interest revenues	1,565	1,513	3,090	3,045
Revenue from contracts with customers	1,551	1,495	3,055	2,986
Interest income	7	7	16	16
Interest expense	(101)	(68)	(194)	(127)
Total revenues, net of interest expense	1,673	1,588	3,300	3,188
Net income	632	543	1,263	1,059
Total assets	22,000	20,000	22,000	20,000
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Non-interest revenues	31	5	50	21
Revenue from contracts with customers	1	2	9	7
Interest income	193	146	412	273
Interest expense	271	205	559	387
Total revenues, net of interest expense	(47)	(54)	(97)	(93)
Net income	(253)	(254)	(741)	(508)
Total assets	$ 19,000	$ 17,000	$ 19,000	$ 17,000