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Securities - Details of Securities (Details) - USD ($) $ in Millions | Dec. 31, 2025 | Dec. 31, 2024
--- | --- | ---
SECURITIES AVAILABLE FOR SALE |  |
Amortized Cost | $ 41,846 | $ 41,302
Gross Unrealized Gains | 267 | 31
Gross Unrealized Losses | 2,517 | 3,626
Fair Value | 39,596 | 37,707
HELD-TO-MATURITY SECURITIES |  |
Amortized Cost | 8,622 | 7,395
Gross Unrealized Gains | 21 | 3
Gross Unrealized Losses | 330 | 561
Fair Value | $ 8,313 | $ 6,837
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration] | Accrued income and other assets | Accrued income and other assets
Debt Securities, Held-to-Maturity, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration] | Accrued income and other assets | Accrued income and other assets
Available-for-sale securities, accrued interest | $ 121 | $ 109
Held-to-maturity securities, accrued interest | 26 | 21
Basis adjustments for securities | 99 | (6)
U.S. Treasury, agencies, and corporations |  |
SECURITIES AVAILABLE FOR SALE |  |
Amortized Cost | 7,842 | 8,928
Gross Unrealized Gains | 61 | 20
Gross Unrealized Losses | 17 | 44
Fair Value | 7,886 | 8,904
Agency residential collateralized mortgage obligations |  |
SECURITIES AVAILABLE FOR SALE |  |
Amortized Cost | 10,269 | 11,409
Gross Unrealized Gains | 4 | 8
Gross Unrealized Losses | 1,708 | 2,193
Fair Value | 8,565 | 9,224
HELD-TO-MATURITY SECURITIES |  |
Amortized Cost | 4,026 | 4,577
Gross Unrealized Gains | 8 | 3
Gross Unrealized Losses | 176 | 332
Fair Value | 3,858 | 4,248
Agency residential mortgage-backed securities |  |
SECURITIES AVAILABLE FOR SALE |  |
Amortized Cost | 19,451 | 16,038
Gross Unrealized Gains | 201 | 3
Gross Unrealized Losses | 457 | 872
Fair Value | 19,195 | 15,169
HELD-TO-MATURITY SECURITIES |  |
Amortized Cost | 2,374 | 151
Gross Unrealized Gains | 12 | 0
Gross Unrealized Losses | 13 | 17
Fair Value | 2,373 | 134
Agency commercial mortgage-backed securities |  |
SECURITIES AVAILABLE FOR SALE |  |
Amortized Cost | 4,284 | 4,927
Gross Unrealized Gains | 1 | 0
Gross Unrealized Losses | 335 | 517
Fair Value | 3,950 | 4,410
HELD-TO-MATURITY SECURITIES |  |
Amortized Cost | 2,121 | 2,333
Gross Unrealized Gains | 1 | 0
Gross Unrealized Losses | 139 | 203
Fair Value | 1,983 | 2,130
Asset-backed securities |  |
HELD-TO-MATURITY SECURITIES |  |
Amortized Cost | 77 | 308
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 2 | 8
Fair Value | 75 | 300
Securities related to purchase of senior notes | 74 | 303
Other securities |  |
HELD-TO-MATURITY SECURITIES |  |
Amortized Cost | 24 | 26
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 0 | 1
Fair Value | $ 24 | $ 25

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