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INVESTMENT SECURITIES - Schedule of Amortized Cost and Fair Value of Investment Securities (Details) - USD ($) $ in Millions | Mar. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Investment securities available for sale |  |
Amortized Cost | $ 34,340 | $ 34,512
Gross Unrealized Gains | 220 | 81
Gross Unrealized Losses | (660) | (843)
Investment securities available for sale | 33,900 | 33,750
Investment in marketable equity securities |  |
Amortized Cost | 78 | 79
Gross Unrealized Gains | 21 | 27
Gross Unrealized Losses | (4) | (5)
Fair Value | 95 | 101
Investment securities held to maturity |  |
Amortized Cost | 10,324 | 10,239
Gross Unrealized Gains | 17 | 2
Gross Unrealized Losses | (1,368) | (1,539)
Fair Value | 8,973 | 8,702
Total investment securities |  |
Amortized Cost | 44,742 | 44,830
Gross Unrealized Gains | 258 | 110
Gross Unrealized Losses | (2,032) | (2,387)
Fair Value | 42,968 | 42,553
U.S. Treasury |  |
Investment securities available for sale |  |
Amortized Cost | 13,105 | 13,897
Gross Unrealized Gains | 55 | 33
Gross Unrealized Losses | (10) | (27)
Investment securities available for sale | 13,150 | 13,903
Investment securities held to maturity |  |
Amortized Cost | 484 | 483
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (25) | (31)
Fair Value | 459 | 452
Government agency |  |
Investment securities available for sale |  |
Amortized Cost | 71 | 79
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (2) | (2)
Investment securities available for sale | 69 | 77
Investment securities held to maturity |  |
Amortized Cost | 1,491 | 1,489
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (91) | (115)
Fair Value | 1,400 | 1,374
Residential mortgage-backed securities |  |
Investment securities available for sale |  |
Amortized Cost | 16,905 | 16,161
Gross Unrealized Gains | 143 | 41
Gross Unrealized Losses | (443) | (582)
Investment securities available for sale | 16,605 | 15,620
Investment securities held to maturity |  |
Amortized Cost | 4,668 | 4,558
Gross Unrealized Gains | 17 | 2
Gross Unrealized Losses | (595) | (682)
Fair Value | 4,090 | 3,878
Commercial mortgage-backed securities |  |
Investment securities available for sale |  |
Amortized Cost | 3,759 | 3,869
Gross Unrealized Gains | 21 | 7
Gross Unrealized Losses | (186) | (210)
Investment securities available for sale | 3,594 | 3,666
Investment securities held to maturity |  |
Amortized Cost | 3,378 | 3,407
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (630) | (678)
Fair Value | 2,748 | 2,729
Corporate bonds |  |
Investment securities available for sale |  |
Amortized Cost | 483 | 489
Gross Unrealized Gains | 1 | 0
Gross Unrealized Losses | (19) | (22)
Investment securities available for sale | 465 | 467
Municipal bonds |  |
Investment securities available for sale |  |
Amortized Cost | 17 | 17
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 0 | 0
Investment securities available for sale | 17 | 17
Supranational securities |  |
Investment securities held to maturity |  |
Amortized Cost | 301 | 300
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (27) | (33)
Fair Value | 274 | 267
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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