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INVESTMENT SECURITIES - Schedule of Amortized Cost and Fair Value of Investment Securities (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Investment securities available for sale |  |
Amortized Cost | $ 34,512 | $ 20,688
Gross Unrealized Gains | 81 | 115
Gross Unrealized Losses | (843) | (867)
Investment securities available for sale | 33,750 | 19,936
Investment in marketable equity securities |  |
Amortized Cost | 79 | 75
Gross Unrealized Gains | 27 | 17
Gross Unrealized Losses | (5) | (8)
Fair Value | 101 | 84
Investment securities held to maturity |  |
Amortized Cost | 10,239 | 9,979
Gross Unrealized Gains | 2 | 0
Gross Unrealized Losses | (1,539) | (1,476)
Fair Value | 8,702 | 8,503
Total investment securities |  |
Amortized Cost | 44,830 | 30,742
Gross Unrealized Gains | 110 | 132
Gross Unrealized Losses | (2,387) | (2,351)
Fair Value | 42,553 | 28,523
U.S. Treasury |  |
Investment securities available for sale |  |
Amortized Cost | 13,897 | 10,554
Gross Unrealized Gains | 33 | 34
Gross Unrealized Losses | (27) | (80)
Investment securities available for sale | 13,903 | 10,508
Investment securities held to maturity |  |
Amortized Cost | 483 | 479
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (31) | (40)
Fair Value | 452 | 439
Government agency |  |
Investment securities available for sale |  |
Amortized Cost | 79 | 120
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (2) | (3)
Investment securities available for sale | 77 | 117
Investment securities held to maturity |  |
Amortized Cost | 1,489 | 1,506
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (115) | (143)
Fair Value | 1,374 | 1,363
Residential mortgage-backed securities |  |
Investment securities available for sale |  |
Amortized Cost | 16,161 | 7,154
Gross Unrealized Gains | 41 | 72
Gross Unrealized Losses | (582) | (540)
Investment securities available for sale | 15,620 | 6,686
Investment securities held to maturity |  |
Amortized Cost | 4,558 | 4,205
Gross Unrealized Gains | 2 | 0
Gross Unrealized Losses | (682) | (644)
Fair Value | 3,878 | 3,561
Commercial mortgage-backed securities |  |
Investment securities available for sale |  |
Amortized Cost | 3,869 | 2,319
Gross Unrealized Gains | 7 | 9
Gross Unrealized Losses | (210) | (197)
Investment securities available for sale | 3,666 | 2,131
Investment securities held to maturity |  |
Amortized Cost | 3,407 | 3,489
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (678) | (614)
Fair Value | 2,729 | 2,875
Corporate bonds |  |
Investment securities available for sale |  |
Amortized Cost | 489 | 529
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (22) | (47)
Investment securities available for sale | 467 | 482
Municipal bonds |  |
Investment securities available for sale |  |
Amortized Cost | 17 | 12
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 0 | 0
Investment securities available for sale | 17 | 12
Supranational securities |  |
Investment securities held to maturity |  |
Amortized Cost | 300 | 298
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (33) | (35)
Fair Value | 267 | 263
Other |  |
Investment securities held to maturity |  |
Amortized Cost | 2 | 2
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 0 | 0
Fair Value | $ 2 | $ 2

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