Reportable Operating Segments (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Segment Reporting Information [Line Items]
Total non-interest revenues	$ 9,536	$ 7,234
Revenue from contracts with customers	7,640	5,654
Interest income	2,520	2,192
Interest expense	321	362
Total revenues net of interest expense	11,735	9,064
Pretax segment income (loss)	2,712	2,993
Total assets	195,862	193,000	$ 188,548
Corporate and Other
Segment Reporting Information [Line Items]
Total non-interest revenues	(49)	(78)
Revenue from contracts with customers	4	(6)
Interest income	42	44
Interest expense	51	75
Total revenues net of interest expense	(58)	(109)
Pretax segment income (loss)	(514)	(212)
Total assets	23,000	55,000
GCSG | Operating Segments
Segment Reporting Information [Line Items]
Total non-interest revenues	5,049	3,809
Revenue from contracts with customers	3,619	2,604
Interest income	2,040	1,808
Interest expense	192	188
Total revenues net of interest expense	6,897	5,429
Pretax segment income (loss)	1,735	2,145
Total assets	101,000	82,000
GCS | Operating Segments
Segment Reporting Information [Line Items]
Total non-interest revenues	3,180	2,442
Revenue from contracts with customers	2,759	2,062
Interest income	436	336
Interest expense	122	116
Total revenues net of interest expense	3,494	2,662
Pretax segment income (loss)	804	675
Total assets	56,000	42,000
GMNS | Operating Segments
Segment Reporting Information [Line Items]
Total non-interest revenues	1,356	1,061
Revenue from contracts with customers	1,258	994
Interest income	2	4
Interest expense	(44)	(17)
Total revenues net of interest expense	1,402	1,082
Pretax segment income (loss)	687	385
Total assets	$ 16,000	$ 14,000