Securities - Details of Securities (Details) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
SECURITIES AVAILABLE FOR SALE
Amortized Cost	$ 46,291	$ 45,893
Gross Unrealized Gains	2	324
Gross Unrealized Losses	6,293	853
Fair Value	40,000	45,364
HELD-TO-MATURITY SECURITIES
Amortized Cost	8,163	7,539
Gross Unrealized Gains	1	157
Gross Unrealized Losses	568	31
Fair Value	7,596	7,665
Debt securities, available for sale, accrued interest	66	59
Debt securities, held to maturity, accrued interest	18	15
U.S. Treasury, agencies and corporations
SECURITIES AVAILABLE FOR SALE
Amortized Cost	10,062	9,573
Gross Unrealized Gains	0	0
Gross Unrealized Losses	676	101
Fair Value	9,386	9,472
Agency residential collateralized mortgage obligations
SECURITIES AVAILABLE FOR SALE
Amortized Cost	20,706	21,430
Gross Unrealized Gains	0	99
Gross Unrealized Losses	3,469	410
Fair Value	17,237	21,119
HELD-TO-MATURITY SECURITIES
Amortized Cost	3,818	2,196
Gross Unrealized Gains	0	33
Gross Unrealized Losses	251	0
Fair Value	3,567	2,229
Agency residential mortgage-backed securities
SECURITIES AVAILABLE FOR SALE
Amortized Cost	4,742	5,137
Gross Unrealized Gains	0	37
Gross Unrealized Losses	757	52
Fair Value	3,985	5,122
HELD-TO-MATURITY SECURITIES
Amortized Cost	185	164
Gross Unrealized Gains	0	6
Gross Unrealized Losses	18	0
Fair Value	167	170
Agency commercial mortgage-backed securities \| Mortgage-backed securities
SECURITIES AVAILABLE FOR SALE
Amortized Cost	10,780	9,753
Gross Unrealized Gains	2	188
Gross Unrealized Losses	1,391	290
Fair Value	9,391	9,651
HELD-TO-MATURITY SECURITIES
Amortized Cost	2,524	2,678
Gross Unrealized Gains	1	118
Gross Unrealized Losses	190	0
Fair Value	2,335	2,796
Asset-backed securities
HELD-TO-MATURITY SECURITIES
Amortized Cost	1,621	2,485
Gross Unrealized Gains	0	0
Gross Unrealized Losses	108	31
Fair Value	1,513	2,454
Debt securities, held-to-maturity, purchase of senior notes	1,600	2,500
Other securities
SECURITIES AVAILABLE FOR SALE
Amortized Cost	1	0
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	1	0
HELD-TO-MATURITY SECURITIES
Amortized Cost	15	16
Gross Unrealized Gains	0	0
Gross Unrealized Losses	1	0
Fair Value	$ 14	$ 16

Debt Securities, Held-To-Maturity, Purchase of Senior Notes

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