Investment Securities - Summary of Remaining Contractual Principal Maturities for Held-to-Maturity Securities (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	$ 91,321
Fair Value	76,169	$ 97,227
One Year or Less - Amortized Cost	69
One Year or Less - Fair Value	68
After One Year to Five Years - Amortized Cost	736
After One Year to Five Years - Fair Value	689
After Five Years to Ten Years - Amortized Cost	4,478
After Five Years to Ten Years - Fair Value	3,986
After Ten Years - Amortized Cost	86,038
After Ten Years - Fair Value	71,426
U.S. agency debentures
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	486
Fair Value	434	615
One Year or Less - Amortized Cost	1
One Year or Less - Fair Value	1
After One Year to Five Years - Amortized Cost	118
After One Year to Five Years - Fair Value	111
After Five Years to Ten Years - Amortized Cost	367
After Five Years to Ten Years - Fair Value	322
After Ten Years - Amortized Cost	0
After Ten Years - Fair Value	0
Agency-issued MBS
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	57,705
Fair Value	48,356	63,676
One Year or Less - Amortized Cost	0
One Year or Less - Fair Value	0
After One Year to Five Years - Amortized Cost	25
After One Year to Five Years - Fair Value	24
After Five Years to Ten Years - Amortized Cost	1,066
After Five Years to Ten Years - Fair Value	994
After Ten Years - Amortized Cost	56,614
After Ten Years - Fair Value	47,338
Agency-issued CMO | Fixed rate
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	10,461
Fair Value	8,576	10,090
One Year or Less - Amortized Cost	0
One Year or Less - Fair Value	0
After One Year to Five Years - Amortized Cost	90
After One Year to Five Years - Fair Value	86
After Five Years to Ten Years - Amortized Cost	129
After Five Years to Ten Years - Fair Value	120
After Ten Years - Amortized Cost	10,242
After Ten Years - Fair Value	8,370
Agency-issued CMO | Variable rate
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	79
Fair Value	77	101
One Year or Less - Amortized Cost	0
One Year or Less - Fair Value	0
After One Year to Five Years - Amortized Cost	0
After One Year to Five Years - Fair Value	0
After Five Years to Ten Years - Amortized Cost	0
After Five Years to Ten Years - Fair Value	0
After Ten Years - Amortized Cost	79
After Ten Years - Fair Value	77
Agency-issued CMBS
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	14,471
Fair Value	11,977	14,721
One Year or Less - Amortized Cost	39
One Year or Less - Fair Value	38
After One Year to Five Years - Amortized Cost	153
After One Year to Five Years - Fair Value	141
After Five Years to Ten Years - Amortized Cost	966
After Five Years to Ten Years - Fair Value	810
After Ten Years - Amortized Cost	13,313
After Ten Years - Fair Value	10,988
Municipal bonds and notes
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	7,416
Fair Value	6,150	7,315
One Year or Less - Amortized Cost	29
One Year or Less - Fair Value	29
After One Year to Five Years - Amortized Cost	235
After One Year to Five Years - Fair Value	224
After Five Years to Ten Years - Amortized Cost	1,362
After Five Years to Ten Years - Fair Value	1,244
After Ten Years - Amortized Cost	5,790
After Ten Years - Fair Value	4,653
Corporate bonds
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	703
Fair Value	599	$ 709
One Year or Less - Amortized Cost	0
One Year or Less - Fair Value	0
After One Year to Five Years - Amortized Cost	115
After One Year to Five Years - Fair Value	103
After Five Years to Ten Years - Amortized Cost	588
After Five Years to Ten Years - Fair Value	496
After Ten Years - Amortized Cost	0
After Ten Years - Fair Value	$ 0
Lower Limit | Held-to-maturity securities
Schedule of Held-to-maturity Securities [Line Items]
Mortgage-backed securities contractual maturities (in years)	10 years
Upper Limit | Held-to-maturity securities
Schedule of Held-to-maturity Securities [Line Items]
Mortgage-backed securities contractual maturities (in years)	30 years