Securities - Details of Securities (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
SECURITIES AVAILABLE FOR SALE
Amortized Cost	$ 46,557	$ 45,893
Gross Unrealized Gains	39	324
Gross Unrealized Losses	2,915	853
Fair Value	43,681	45,364
HELD-TO-MATURITY SECURITIES
Amortized Cost	6,871	7,539
Gross Unrealized Gains	7	157
Gross Unrealized Losses	191	31
Fair Value	6,687	7,665
Accrued interest	193	198
U.S. Treasury, agencies and corporations
SECURITIES AVAILABLE FOR SALE
Amortized Cost	10,054	9,573
Gross Unrealized Gains	0	0
Gross Unrealized Losses	416	101
Fair Value	9,638	9,472
Agency residential collateralized mortgage obligations
SECURITIES AVAILABLE FOR SALE
Amortized Cost	22,255	21,430
Gross Unrealized Gains	3	99
Gross Unrealized Losses	1,619	410
Fair Value	20,639	21,119
HELD-TO-MATURITY SECURITIES
Amortized Cost	1,983	2,196
Gross Unrealized Gains	0	33
Gross Unrealized Losses	67	0
Fair Value	1,916	2,229
Agency residential mortgage-backed securities
SECURITIES AVAILABLE FOR SALE
Amortized Cost	5,075	5,137
Gross Unrealized Gains	9	37
Gross Unrealized Losses	340	52
Fair Value	4,744	5,122
HELD-TO-MATURITY SECURITIES
Amortized Cost	152	164
Gross Unrealized Gains	0	6
Gross Unrealized Losses	3	0
Fair Value	150	170
Asset-backed securities (c)
HELD-TO-MATURITY SECURITIES
Amortized Cost	2,172	2,485
Gross Unrealized Gains	0	0
Gross Unrealized Losses	89	31
Fair Value	2,082	2,454
Debt securities, held-to-maturity, purchase of senior notes	2,200	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	0	0
Fair Value	15	16
Mortgage-backed securities \| Agency commercial mortgage-backed securities
SECURITIES AVAILABLE FOR SALE
Amortized Cost	9,172	9,753
Gross Unrealized Gains	27	188
Gross Unrealized Losses	540	290
Fair Value	8,659	9,651
HELD-TO-MATURITY SECURITIES
Amortized Cost	2,549	2,678
Gross Unrealized Gains	7	118
Gross Unrealized Losses	32	0
Fair Value	2,524	2,796
Securities available for sale
HELD-TO-MATURITY SECURITIES
Accrued interest	64	59
Securities held-to-maturity
HELD-TO-MATURITY SECURITIES
Accrued interest	$ 14	$ 15

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

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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