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INVESTMENT SECURITIES - Schedule of Amortized Cost and Fair Value of Investment Securities (Details) - USD ($) $ in Millions | Dec. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Investment securities available for sale |  |
Amortized Cost | $ 31,952 | $ 34,512
Gross Unrealized Gains | 341 | 81
Gross Unrealized Losses | (503) | (843)
Investment securities available for sale | 31,790 | 33,750
Investment in marketable equity securities |  |
Amortized Cost | 83 | 79
Gross Unrealized Gains | 44 | 27
Gross Unrealized Losses | 0 | (5)
Fair Value | 127 | 101
Investment securities held to maturity |  |
Amortized Cost | 9,647 | 10,239
Gross Unrealized Gains | 32 | 2
Gross Unrealized Losses | (1,188) | (1,539)
Fair Value | 8,491 | 8,702
Total investment securities |  |
Amortized Cost | 41,682 | 44,830
Gross Unrealized Gains | 417 | 110
Gross Unrealized Losses | (1,691) | (2,387)
Fair Value | 40,408 | 42,553
U.S. Treasury |  |
Investment securities available for sale |  |
Amortized Cost | 10,624 | 13,897
Gross Unrealized Gains | 50 | 33
Gross Unrealized Losses | (1) | (27)
Investment securities available for sale | 10,673 | 13,903
Investment securities held to maturity |  |
Amortized Cost | 388 | 483
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (15) | (31)
Fair Value | 373 | 452
Government agency |  |
Investment securities available for sale |  |
Amortized Cost | 44 | 79
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (1) | (2)
Investment securities available for sale | 43 | 77
Investment securities held to maturity |  |
Amortized Cost | 1,225 | 1,489
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (55) | (115)
Fair Value | 1,170 | 1,374
Residential mortgage-backed securities |  |
Investment securities available for sale |  |
Amortized Cost | 17,683 | 16,161
Gross Unrealized Gains | 263 | 41
Gross Unrealized Losses | (323) | (582)
Investment securities available for sale | 17,623 | 15,620
Investment securities held to maturity |  |
Amortized Cost | 4,450 | 4,558
Gross Unrealized Gains | 32 | 2
Gross Unrealized Losses | (490) | (682)
Fair Value | 3,992 | 3,878
Commercial mortgage-backed securities |  |
Investment securities available for sale |  |
Amortized Cost | 3,444 | 3,869
Gross Unrealized Gains | 28 | 7
Gross Unrealized Losses | (173) | (210)
Investment securities available for sale | 3,299 | 3,666
Investment securities held to maturity |  |
Amortized Cost | 3,337 | 3,407
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (608) | (678)
Fair Value | 2,729 | 2,729
Corporate bonds |  |
Investment securities available for sale |  |
Amortized Cost | 145 | 489
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (5) | (22)
Investment securities available for sale | 140 | 467
Municipal bonds |  |
Investment securities available for sale |  |
Amortized Cost | 12 | 17
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 0 | 0
Investment securities available for sale | 12 | 17
Supranational securities |  |
Investment securities held to maturity |  |
Amortized Cost | 246 | 300
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (20) | (33)
Fair Value | 226 | 267
Other |  |
Investment securities held to maturity |  |
Amortized Cost | 1 | 2
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 0 | 0
Fair Value | $ 1 | $ 2

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