Securities - Schedule of Details of Securities (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
SECURITIES AVAILABLE FOR SALE
Amortized Cost	$ 45,179	$ 45,552
Gross Unrealized Gains	5	2
Gross Unrealized Losses	5,686	6,437
Fair Value	39,498	39,117
HELD-TO-MATURITY SECURITIES
Total	9,561	8,710
Gross Unrealized Gains	17	6
Gross Unrealized Losses	493	603
Fair Value	9,085	8,113
Debt securities, available for sale, accrued interest	66	67
Debt securities, held to maturity, accrued interest	24	88
U.S. Treasury, agencies and corporations
SECURITIES AVAILABLE FOR SALE
Amortized Cost	10,027	10,044
Gross Unrealized Gains	0	0
Gross Unrealized Losses	513	629
Fair Value	9,514	9,415
Agency residential collateralized mortgage obligations
SECURITIES AVAILABLE FOR SALE
Amortized Cost	19,770	20,180
Gross Unrealized Gains	0	0
Gross Unrealized Losses	3,345	3,747
Fair Value	16,425	16,433
HELD-TO-MATURITY SECURITIES
Total	5,566	4,586
Gross Unrealized Gains	15	5
Gross Unrealized Losses	232	283
Fair Value	5,349	4,308
Agency residential mortgage-backed securities \| Mortgage-backed securities
SECURITIES AVAILABLE FOR SALE
Amortized Cost	4,534	4,616
Gross Unrealized Gains	0	0
Gross Unrealized Losses	634	696
Fair Value	3,900	3,920
HELD-TO-MATURITY SECURITIES
Total	177	181
Gross Unrealized Gains	0	0
Gross Unrealized Losses	12	16
Fair Value	165	165
Agency commercial mortgage-backed securities \| Mortgage-backed securities
SECURITIES AVAILABLE FOR SALE
Amortized Cost	10,848	10,712
Gross Unrealized Gains	5	2
Gross Unrealized Losses	1,194	1,365
Fair Value	9,659	9,349
HELD-TO-MATURITY SECURITIES
Total	2,584	2,522
Gross Unrealized Gains	2	1
Gross Unrealized Losses	184	208
Fair Value	2,402	2,315
Asset-backed securities
HELD-TO-MATURITY SECURITIES
Total	1,219	1,407
Gross Unrealized Gains	0	0
Gross Unrealized Losses	64	96
Fair Value	1,155	1,311
Debt securities, held-to-maturity, purchase of senior notes	1,200	1,400
Other securities
SECURITIES AVAILABLE FOR SALE
Amortized Cost	0	0
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	0	0
HELD-TO-MATURITY SECURITIES
Total	15	14
Gross Unrealized Gains	0	0
Gross Unrealized Losses	1	0
Fair Value	$ 14	$ 14

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