Investment Securities - Schedule of Contractual Maturities of Debt Securities (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Contractual Maturities Of Debt Investment Securities [Line Items]
Available for sale, under 1 year, amortized cost	$ 6,565
Available for sale, under 1 year, fair value	6,537
Available for sale, 1 to 5 years, amortized cost	21,917
Available for sale, 1 to 5 years, fair value	21,042
Available for sale, 6 to 10 years, amortized cost	13,462
Available for sale, 6 to 10 years, fair value	13,338
Available for sale, over 10 years, amortized cost	4,652
Available for sale, over 10 years, fair value	4,537
Available for sale, amortized cost	46,596	$ 73,440
Available for sale, fair value	45,454	73,399
Held to maturity, amortized cost	64,261	42,430
Investment securities held-to-maturity	60,103	42,271
Direct obligations
Contractual Maturities Of Debt Investment Securities [Line Items]
Available for sale, under 1 year, amortized cost	2,049
Available for sale, under 1 year, fair value	2,039
Available for sale, 1 to 5 years, amortized cost	7,112
Available for sale, 1 to 5 years, fair value	6,800
Available for sale, 6 to 10 years, amortized cost	559
Available for sale, 6 to 10 years, fair value	572
Available for sale, over 10 years, amortized cost	0
Available for sale, over 10 years, fair value	0
Available for sale, amortized cost	9,720	18,111
Available for sale, fair value	9,411	17,939
Held to maturity, under 1 year, amortized cost	400
Held to maturity, under 1 year, fair value	400
Held to maturity, 1 to 5 years, amortized cost	10,985
Held to maturity, 1 to 5 years, fair value	10,911
Held to maturity, 6 to 10 years, amortized cost	24
Held to maturity, 6 to 10 years, fair value	23
Held to maturity, over 10 years, amortized cost	15
Held to maturity, over 10 years, fair value	15
Held to maturity, amortized cost	11,424	2,170
Investment securities held-to-maturity	11,349	2,180
Mortgage-backed securities
Contractual Maturities Of Debt Investment Securities [Line Items]
Available for sale, under 1 year, amortized cost	56
Available for sale, under 1 year, fair value	56
Available for sale, 1 to 5 years, amortized cost	549
Available for sale, 1 to 5 years, fair value	548
Available for sale, 6 to 10 years, amortized cost	7,862
Available for sale, 6 to 10 years, fair value	7,793
Available for sale, over 10 years, amortized cost	1,942
Available for sale, over 10 years, fair value	1,874
Available for sale, amortized cost	10,409	18,154
Available for sale, fair value	10,271	18,208
Held to maturity, under 1 year, amortized cost	157
Held to maturity, under 1 year, fair value	151
Held to maturity, 1 to 5 years, amortized cost	556
Held to maturity, 1 to 5 years, fair value	540
Held to maturity, 6 to 10 years, amortized cost	4,706
Held to maturity, 6 to 10 years, fair value	4,141
Held to maturity, over 10 years, amortized cost	36,241
Held to maturity, over 10 years, fair value	32,976
Held to maturity, amortized cost	41,660	33,481
Investment securities held-to-maturity	37,808	33,265
Total U.S. Treasury and federal agencies
Contractual Maturities Of Debt Investment Securities [Line Items]
Available for sale, under 1 year, amortized cost	2,105
Available for sale, under 1 year, fair value	2,095
Available for sale, 1 to 5 years, amortized cost	7,661
Available for sale, 1 to 5 years, fair value	7,348
Available for sale, 6 to 10 years, amortized cost	8,421
Available for sale, 6 to 10 years, fair value	8,365
Available for sale, over 10 years, amortized cost	1,942
Available for sale, over 10 years, fair value	1,874
Available for sale, amortized cost	20,129	36,265
Available for sale, fair value	19,682	36,147
Held to maturity, under 1 year, amortized cost	557
Held to maturity, under 1 year, fair value	551
Held to maturity, 1 to 5 years, amortized cost	11,541
Held to maturity, 1 to 5 years, fair value	11,451
Held to maturity, 6 to 10 years, amortized cost	4,730
Held to maturity, 6 to 10 years, fair value	4,164
Held to maturity, over 10 years, amortized cost	36,256
Held to maturity, over 10 years, fair value	32,991
Held to maturity, amortized cost	53,084	35,651
Investment securities held-to-maturity	49,157	35,445
Mortgage-backed securities
Contractual Maturities Of Debt Investment Securities [Line Items]
Available for sale, under 1 year, amortized cost	174
Available for sale, under 1 year, fair value	174
Available for sale, 1 to 5 years, amortized cost	388
Available for sale, 1 to 5 years, fair value	386
Available for sale, 6 to 10 years, amortized cost	28
Available for sale, 6 to 10 years, fair value	27
Available for sale, over 10 years, amortized cost	1,382
Available for sale, over 10 years, fair value	1,372
Available for sale, amortized cost	1,972	1,986
Available for sale, fair value	1,959	1,995
Asset-backed securities
Contractual Maturities Of Debt Investment Securities [Line Items]
Available for sale, under 1 year, amortized cost	265
Available for sale, under 1 year, fair value	260
Available for sale, 1 to 5 years, amortized cost	810
Available for sale, 1 to 5 years, fair value	801
Available for sale, 6 to 10 years, amortized cost	459
Available for sale, 6 to 10 years, fair value	453
Available for sale, over 10 years, amortized cost	367
Available for sale, over 10 years, fair value	362
Available for sale, amortized cost	1,901	2,087
Available for sale, fair value	1,876	2,087
Non-U.S. sovereign, supranational and non-U.S. agency
Contractual Maturities Of Debt Investment Securities [Line Items]
Available for sale, under 1 year, amortized cost	3,345
Available for sale, under 1 year, fair value	3,335
Available for sale, 1 to 5 years, amortized cost	9,142
Available for sale, 1 to 5 years, fair value	8,800
Available for sale, 6 to 10 years, amortized cost	2,813
Available for sale, 6 to 10 years, fair value	2,792
Available for sale, over 10 years, amortized cost	0
Available for sale, over 10 years, fair value	0
Available for sale, amortized cost	15,300	23,533
Available for sale, fair value	14,927	23,547
Held to maturity, under 1 year, amortized cost	546
Held to maturity, under 1 year, fair value	543
Held to maturity, 1 to 5 years, amortized cost	5,303
Held to maturity, 1 to 5 years, fair value	5,186
Held to maturity, 6 to 10 years, amortized cost	594
Held to maturity, 6 to 10 years, fair value	586
Held to maturity, over 10 years, amortized cost	0
Held to maturity, over 10 years, fair value	0
Held to maturity, amortized cost	6,443	1,564
Investment securities held-to-maturity	6,315	1,555
Other
Contractual Maturities Of Debt Investment Securities [Line Items]
Available for sale, under 1 year, amortized cost	267
Available for sale, under 1 year, fair value	266
Available for sale, 1 to 5 years, amortized cost	1,940
Available for sale, 1 to 5 years, fair value	1,812
Available for sale, 6 to 10 years, amortized cost	122
Available for sale, 6 to 10 years, fair value	103
Available for sale, over 10 years, amortized cost	29
Available for sale, over 10 years, fair value	23
Available for sale, amortized cost	2,358	3,113
Available for sale, fair value	2,204	3,098
Total non-U.S. debt securities
Contractual Maturities Of Debt Investment Securities [Line Items]
Available for sale, under 1 year, amortized cost	4,051
Available for sale, under 1 year, fair value	4,035
Available for sale, 1 to 5 years, amortized cost	12,280
Available for sale, 1 to 5 years, fair value	11,799
Available for sale, 6 to 10 years, amortized cost	3,422
Available for sale, 6 to 10 years, fair value	3,375
Available for sale, over 10 years, amortized cost	1,778
Available for sale, over 10 years, fair value	1,757
Available for sale, amortized cost	21,531	30,719
Available for sale, fair value	20,966	30,727
Held to maturity, under 1 year, amortized cost	546
Held to maturity, under 1 year, fair value	543
Held to maturity, 1 to 5 years, amortized cost	5,303
Held to maturity, 1 to 5 years, fair value	5,186
Held to maturity, 6 to 10 years, amortized cost	594
Held to maturity, 6 to 10 years, fair value	586
Held to maturity, over 10 years, amortized cost	0
Held to maturity, over 10 years, fair value	0
Held to maturity, amortized cost	6,443	1,564
Investment securities held-to-maturity	6,315	1,555
Student loans
Contractual Maturities Of Debt Investment Securities [Line Items]
Available for sale, under 1 year, amortized cost	64
Available for sale, under 1 year, fair value	65
Available for sale, 1 to 5 years, amortized cost	0
Available for sale, 1 to 5 years, fair value	0
Available for sale, 6 to 10 years, amortized cost	0
Available for sale, 6 to 10 years, fair value	0
Available for sale, over 10 years, amortized cost	88
Available for sale, over 10 years, fair value	85
Available for sale, amortized cost	152	209
Available for sale, fair value	150	211
Held to maturity, under 1 year, amortized cost	332
Held to maturity, under 1 year, fair value	319
Held to maturity, 1 to 5 years, amortized cost	13
Held to maturity, 1 to 5 years, fair value	13
Held to maturity, 6 to 10 years, amortized cost	960
Held to maturity, 6 to 10 years, fair value	941
Held to maturity, over 10 years, amortized cost	3,163
Held to maturity, over 10 years, fair value	3,072
Held to maturity, amortized cost	4,468	4,908
Investment securities held-to-maturity	4,345	4,942
Collateralized loan obligations
Contractual Maturities Of Debt Investment Securities [Line Items]
Available for sale, under 1 year, amortized cost	108
Available for sale, under 1 year, fair value	106
Available for sale, 1 to 5 years, amortized cost	485
Available for sale, 1 to 5 years, fair value	477
Available for sale, 6 to 10 years, amortized cost	1,197
Available for sale, 6 to 10 years, fair value	1,177
Available for sale, over 10 years, amortized cost	588
Available for sale, over 10 years, fair value	574
Available for sale, amortized cost	2,378	2,155
Available for sale, fair value	2,334	2,155
Non-agency CMBS and RMBS
Contractual Maturities Of Debt Investment Securities [Line Items]
Available for sale, under 1 year, amortized cost	0
Available for sale, under 1 year, fair value	0
Available for sale, 1 to 5 years, amortized cost	0
Available for sale, 1 to 5 years, fair value	0
Available for sale, 6 to 10 years, amortized cost	0
Available for sale, 6 to 10 years, fair value	0
Available for sale, over 10 years, amortized cost	200
Available for sale, over 10 years, fair value	195
Available for sale, amortized cost	200	52
Available for sale, fair value	195	52
Held to maturity, under 1 year, amortized cost	181
Held to maturity, under 1 year, fair value	188
Held to maturity, 1 to 5 years, amortized cost	11
Held to maturity, 1 to 5 years, fair value	12
Held to maturity, 6 to 10 years, amortized cost	0
Held to maturity, 6 to 10 years, fair value	0
Held to maturity, over 10 years, amortized cost	74
Held to maturity, over 10 years, fair value	86
Held to maturity, amortized cost	266	307
Investment securities held-to-maturity	286	329
Other
Contractual Maturities Of Debt Investment Securities [Line Items]
Available for sale, under 1 year, amortized cost	0
Available for sale, under 1 year, fair value	0
Available for sale, 1 to 5 years, amortized cost	90
Available for sale, 1 to 5 years, fair value	89
Available for sale, 6 to 10 years, amortized cost	0
Available for sale, 6 to 10 years, fair value	0
Available for sale, over 10 years, amortized cost	0
Available for sale, over 10 years, fair value	0
Available for sale, amortized cost	90	90
Available for sale, fair value	89	91
Total asset-backed securities
Contractual Maturities Of Debt Investment Securities [Line Items]
Available for sale, under 1 year, amortized cost	172
Available for sale, under 1 year, fair value	171
Available for sale, 1 to 5 years, amortized cost	575
Available for sale, 1 to 5 years, fair value	566
Available for sale, 6 to 10 years, amortized cost	1,197
Available for sale, 6 to 10 years, fair value	1,177
Available for sale, over 10 years, amortized cost	876
Available for sale, over 10 years, fair value	854
Available for sale, amortized cost	2,820	2,506
Available for sale, fair value	2,768	2,509
Held to maturity, under 1 year, amortized cost	513
Held to maturity, under 1 year, fair value	507
Held to maturity, 1 to 5 years, amortized cost	24
Held to maturity, 1 to 5 years, fair value	25
Held to maturity, 6 to 10 years, amortized cost	960
Held to maturity, 6 to 10 years, fair value	941
Held to maturity, over 10 years, amortized cost	3,237
Held to maturity, over 10 years, fair value	3,158
Held to maturity, amortized cost	4,734	5,215
Investment securities held-to-maturity	4,631	5,271
State and political subdivisions
Contractual Maturities Of Debt Investment Securities [Line Items]
Available for sale, under 1 year, amortized cost	175
Available for sale, under 1 year, fair value	175
Available for sale, 1 to 5 years, amortized cost	404
Available for sale, 1 to 5 years, fair value	401
Available for sale, 6 to 10 years, amortized cost	407
Available for sale, 6 to 10 years, fair value	406
Available for sale, over 10 years, amortized cost	56
Available for sale, over 10 years, fair value	52
Available for sale, amortized cost	1,042	1,216
Available for sale, fair value	1,034	1,272
Other U.S. debt securities
Contractual Maturities Of Debt Investment Securities [Line Items]
Available for sale, under 1 year, amortized cost	62
Available for sale, under 1 year, fair value	61
Available for sale, 1 to 5 years, amortized cost	997
Available for sale, 1 to 5 years, fair value	928
Available for sale, 6 to 10 years, amortized cost	15
Available for sale, 6 to 10 years, fair value	15
Available for sale, over 10 years, amortized cost	0
Available for sale, over 10 years, fair value	0
Available for sale, amortized cost	1,074	2,734
Available for sale, fair value	1,004	$ 2,744
Total
Contractual Maturities Of Debt Investment Securities [Line Items]
Held to maturity, under 1 year, amortized cost	1,616
Held to maturity, under 1 year, fair value	1,601
Held to maturity, 1 to 5 years, amortized cost	16,868
Held to maturity, 1 to 5 years, fair value	16,662
Held to maturity, 6 to 10 years, amortized cost	6,284
Held to maturity, 6 to 10 years, fair value	5,691
Held to maturity, over 10 years, amortized cost	39,493
Held to maturity, over 10 years, fair value	36,149
Held to maturity, amortized cost	64,261
Investment securities held-to-maturity	$ 60,103