Securities - Details of Securities (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
SECURITIES AVAILABLE FOR SALE
Amortized Cost	$ 46,601	$ 45,893
Gross Unrealized Gains	17	324
Gross Unrealized Losses	4,181	853
Fair Value	42,437	45,364
HELD-TO-MATURITY SECURITIES
Amortized Cost	8,186	7,539
Gross Unrealized Gains	6	157
Gross Unrealized Losses	312	31
Fair Value	7,880	7,665
Accrued interest	233	198
Securities available for sale
HELD-TO-MATURITY SECURITIES
Accrued interest	66	59
Securities held-to-maturity
HELD-TO-MATURITY SECURITIES
Accrued interest	17	15
U.S. Treasury, agencies and corporations
SECURITIES AVAILABLE FOR SALE
Amortized Cost	10,080	9,573
Gross Unrealized Gains	0	0
Gross Unrealized Losses	491	101
Fair Value	9,589	9,472
Agency residential collateralized mortgage obligations
SECURITIES AVAILABLE FOR SALE
Amortized Cost	21,419	21,430
Gross Unrealized Gains	0	99
Gross Unrealized Losses	2,375	410
Fair Value	19,044	21,119
HELD-TO-MATURITY SECURITIES
Amortized Cost	3,708	2,196
Gross Unrealized Gains	6	33
Gross Unrealized Losses	100	0
Fair Value	3,614	2,229
Agency residential mortgage-backed securities
SECURITIES AVAILABLE FOR SALE
Amortized Cost	4,891	5,137
Gross Unrealized Gains	2	37
Gross Unrealized Losses	514	52
Fair Value	4,379	5,122
HELD-TO-MATURITY SECURITIES
Amortized Cost	144	164
Gross Unrealized Gains	0	6
Gross Unrealized Losses	7	0
Fair Value	137	170
Agency commercial mortgage-backed securities \| Mortgage-backed securities
SECURITIES AVAILABLE FOR SALE
Amortized Cost	10,211	9,753
Gross Unrealized Gains	14	188
Gross Unrealized Losses	801	290
Fair Value	9,424	9,651
HELD-TO-MATURITY SECURITIES
Amortized Cost	2,449	2,678
Gross Unrealized Gains	0	118
Gross Unrealized Losses	90	0
Fair Value	2,359	2,796
Asset-backed securities
HELD-TO-MATURITY SECURITIES
Amortized Cost	1,870	2,485
Gross Unrealized Gains	0	0
Gross Unrealized Losses	114	31
Fair Value	1,756	2,454
Debt securities, held-to-maturity, purchase of senior notes	1,900	2,500
Other securities
SECURITIES AVAILABLE FOR SALE
Amortized Cost	0	0
Gross Unrealized Gains	1	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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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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