Securities - Schedule of Details of Securities (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
SECURITIES AVAILABLE FOR SALE
Amortized Cost	$ 43,089	$ 42,695
Gross Unrealized Gains	16	10
Gross Unrealized Losses	5,645	5,520
Fair Value	37,460	37,185
HELD-TO-MATURITY SECURITIES
Total	7,968	8,575
Gross Unrealized Gains	1	10
Gross Unrealized Losses	611	529
Fair Value	7,358	8,056
Debt securities, available for sale, accrued interest	74	64
Debt securities, held to maturity, accrued interest	23	25
U.S. Treasury, agencies and corporations
SECURITIES AVAILABLE FOR SALE
Amortized Cost	9,128	9,300
Gross Unrealized Gains	5	6
Gross Unrealized Losses	138	280
Fair Value	8,995	9,026
Agency residential collateralized mortgage obligations
SECURITIES AVAILABLE FOR SALE
Amortized Cost	18,826	18,911
Gross Unrealized Gains	9	4
Gross Unrealized Losses	3,559	3,437
Fair Value	15,276	15,478
HELD-TO-MATURITY SECURITIES
Total	4,879	5,170
Gross Unrealized Gains	1	9
Gross Unrealized Losses	356	283
Fair Value	4,524	4,896
Agency residential mortgage-backed securities
SECURITIES AVAILABLE FOR SALE
Amortized Cost	4,878	4,189
Gross Unrealized Gains	2	0
Gross Unrealized Losses	637	600
Fair Value	4,243	3,589
HELD-TO-MATURITY SECURITIES
Total	157	165
Gross Unrealized Gains	0	0
Gross Unrealized Losses	17	13
Fair Value	140	152
Agency commercial mortgage-backed securities
SECURITIES AVAILABLE FOR SALE
Amortized Cost	10,257	10,295
Gross Unrealized Gains	0	0
Gross Unrealized Losses	1,311	1,203
Fair Value	8,946	9,092
HELD-TO-MATURITY SECURITIES
Total	2,413	2,473
Gross Unrealized Gains	0	1
Gross Unrealized Losses	225	204
Fair Value	2,188	2,270
Asset-backed securities
HELD-TO-MATURITY SECURITIES
Total	493	738
Gross Unrealized Gains	0	0
Gross Unrealized Losses	12	29
Fair Value	481	709
Debt securities, held-to-maturity, purchase of senior notes	487	731
Other securities
HELD-TO-MATURITY SECURITIES
Total	26	29
Gross Unrealized Gains	0	0
Gross Unrealized Losses	1	0
Fair Value	$ 25	$ 29

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