Securities - Schedule of Details of Securities (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
SECURITIES AVAILABLE FOR SALE
Amortized Cost	$ 41,004	$ 41,846
Gross Unrealized Gains	142	267
Gross Unrealized Losses	2,687	2,517
Fair Value	38,459	39,596
HELD-TO-MATURITY SECURITIES
Amortized Cost	9,515	8,622
Gross Unrealized Gains	7	21
Gross Unrealized Losses	398	330
Fair Value	9,124	8,313
Debt securities, available for sale, accrued interest	115	121
Debt securities, held to maturity, accrued interest	32	26
Basis adjustments for securities	(26)	99
U.S. Treasury, agencies and corporations
SECURITIES AVAILABLE FOR SALE
Amortized Cost	7,102	7,842
Gross Unrealized Gains	11	61
Gross Unrealized Losses	38	17
Fair Value	7,075	7,886
Agency residential collateralized mortgage obligations
SECURITIES AVAILABLE FOR SALE
Amortized Cost	9,726	10,269
Gross Unrealized Gains	9	4
Gross Unrealized Losses	1,740	1,708
Fair Value	7,995	8,565
HELD-TO-MATURITY SECURITIES
Amortized Cost	3,754	4,026
Gross Unrealized Gains	2	8
Gross Unrealized Losses	208	176
Fair Value	3,548	3,858
Agency residential mortgage-backed securities
SECURITIES AVAILABLE FOR SALE
Amortized Cost	20,028	19,451
Gross Unrealized Gains	122	201
Gross Unrealized Losses	542	457
Fair Value	19,608	19,195
HELD-TO-MATURITY SECURITIES
Amortized Cost	3,935	2,374
Gross Unrealized Gains	5	12
Gross Unrealized Losses	44	13
Fair Value	3,896	2,373
Agency commercial mortgage-backed securities
SECURITIES AVAILABLE FOR SALE
Amortized Cost	4,148	4,284
Gross Unrealized Gains	0	1
Gross Unrealized Losses	367	335
Fair Value	3,781	3,950
HELD-TO-MATURITY SECURITIES
Amortized Cost	1,786	2,121
Gross Unrealized Gains	0	1
Gross Unrealized Losses	144	139
Fair Value	1,642	1,983
Asset-backed securities
HELD-TO-MATURITY SECURITIES
Amortized Cost	19	77
Gross Unrealized Gains	0	0
Gross Unrealized Losses	1	2
Fair Value	18	75
Debt securities, held-to-maturity, purchase of senior notes	16	74
Other securities
HELD-TO-MATURITY SECURITIES
Amortized Cost	21	24
Gross Unrealized Gains	0	0
Gross Unrealized Losses	1	0
Fair Value	$ 20	$ 24

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