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INVESTMENT SECURITIES - Schedule of Fair Values and Unrealized Losses of Securities, Segregated by Length of Impairment (Details) $ in Millions | Dec. 31, 2025 USD ($) security | Dec. 31, 2024 USD ($) security
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Schedule Of Securities [Line Items] |  |
Debt securities, available-for-sale, less than 12 months, number of positions | security | 12 | 43
Debt securities, available-for-sale, 12 months or longer, number of positions | security | 203 | 213
Debt securities, available-for-sale, number of positions | security | 215 | 256
Debt securities, available-for-sale, less than 12 months | $ 251 | $ 1,104
Debt securities, available-for-sale, 12 months or longer | 1,322 | 1,670
Debt securities, available-for-sale, unrealized loss position | 1,573 | 2,774
Debt securities, available-for-sale, less than 12 months, accumulated loss | (1) | (10)
Debt securities, available-for-sale, 12 months or longer, accumulated loss | (84) | (148)
Debt securities, available-for-sale, accumulated loss | $ (85) | $ (158)
U.S. Treasury |  |
Schedule Of Securities [Line Items] |  |
Debt securities, available-for-sale, less than 12 months, number of positions | security |  | 3
Debt securities, available-for-sale, 12 months or longer, number of positions | security |  | 2
Debt securities, available-for-sale, number of positions | security |  | 5
Debt securities, available-for-sale, less than 12 months |  | $ 74
Debt securities, available-for-sale, 12 months or longer |  | 75
Debt securities, available-for-sale, unrealized loss position |  | 149
Debt securities, available-for-sale, less than 12 months, accumulated loss |  | (1)
Debt securities, available-for-sale, 12 months or longer, accumulated loss |  | 0
Debt securities, available-for-sale, accumulated loss |  | $ (1)
U.S. government agencies |  |
Schedule Of Securities [Line Items] |  |
Debt securities, available-for-sale, less than 12 months, number of positions | security | 5 | 6
Debt securities, available-for-sale, 12 months or longer, number of positions | security | 12 | 12
Debt securities, available-for-sale, number of positions | security | 17 | 18
Debt securities, available-for-sale, less than 12 months | $ 8 | $ 11
Debt securities, available-for-sale, 12 months or longer | 20 | 25
Debt securities, available-for-sale, unrealized loss position | 28 | 36
Debt securities, available-for-sale, less than 12 months, accumulated loss | 0 | 0
Debt securities, available-for-sale, 12 months or longer, accumulated loss | 0 | 0
Debt securities, available-for-sale, accumulated loss | $ 0 | $ 0
U.S. GSE |  |
Schedule Of Securities [Line Items] |  |
Debt securities, available-for-sale, less than 12 months, number of positions | security | 2 | 2
Debt securities, available-for-sale, 12 months or longer, number of positions | security | 3 | 7
Debt securities, available-for-sale, number of positions | security | 5 | 9
Debt securities, available-for-sale, less than 12 months | $ 65 | $ 75
Debt securities, available-for-sale, 12 months or longer | 51 | 126
Debt securities, available-for-sale, unrealized loss position | 116 | 201
Debt securities, available-for-sale, less than 12 months, accumulated loss | 0 | 0
Debt securities, available-for-sale, 12 months or longer, accumulated loss | 0 | (2)
Debt securities, available-for-sale, accumulated loss | $ 0 | $ (2)
Agency MBS |  |
Schedule Of Securities [Line Items] |  |
Debt securities, available-for-sale, less than 12 months, number of positions | security | 1 | 9
Debt securities, available-for-sale, 12 months or longer, number of positions | security | 90 | 92
Debt securities, available-for-sale, number of positions | security | 91 | 101
Debt securities, available-for-sale, less than 12 months | $ 46 | $ 235
Debt securities, available-for-sale, 12 months or longer | 251 | 355
Debt securities, available-for-sale, unrealized loss position | 297 | 590
Debt securities, available-for-sale, less than 12 months, accumulated loss | 0 | (1)
Debt securities, available-for-sale, 12 months or longer, accumulated loss | (8) | (19)
Debt securities, available-for-sale, accumulated loss | $ (8) | $ (20)
Agency CMO |  |
Schedule Of Securities [Line Items] |  |
Debt securities, available-for-sale, less than 12 months, number of positions | security | 0 | 0
Debt securities, available-for-sale, 12 months or longer, number of positions | security | 64 | 66
Debt securities, available-for-sale, number of positions | security | 64 | 66
Debt securities, available-for-sale, less than 12 months | $ 0 | $ 0
Debt securities, available-for-sale, 12 months or longer | 601 | 698
Debt securities, available-for-sale, unrealized loss position | 601 | 698
Debt securities, available-for-sale, less than 12 months, accumulated loss | 0 | 0
Debt securities, available-for-sale, 12 months or longer, accumulated loss | (61) | (98)
Debt securities, available-for-sale, accumulated loss | $ (61) | $ (98)
Agency commercial MBS |  |
Schedule Of Securities [Line Items] |  |
Debt securities, available-for-sale, less than 12 months, number of positions | security | 4 | 23
Debt securities, available-for-sale, 12 months or longer, number of positions | security | 22 | 20
Debt securities, available-for-sale, number of positions | security | 26 | 43
Debt securities, available-for-sale, less than 12 months | $ 132 | $ 709
Debt securities, available-for-sale, 12 months or longer | 371 | 359
Debt securities, available-for-sale, unrealized loss position | 503 | 1,068
Debt securities, available-for-sale, less than 12 months, accumulated loss | (1) | (8)
Debt securities, available-for-sale, 12 months or longer, accumulated loss | (14) | (27)
Debt securities, available-for-sale, accumulated loss | $ (15) | $ (35)
States of the U.S. and political subdivisions (municipals) |  |
Schedule Of Securities [Line Items] |  |
Debt securities, available-for-sale, less than 12 months, number of positions | security | 0 | 0
Debt securities, available-for-sale, 12 months or longer, number of positions | security | 9 | 10
Debt securities, available-for-sale, number of positions | security | 9 | 10
Debt securities, available-for-sale, less than 12 months | $ 0 | $ 0
Debt securities, available-for-sale, 12 months or longer | 19 | 22
Debt securities, available-for-sale, unrealized loss position | 19 | 22
Debt securities, available-for-sale, less than 12 months, accumulated loss | 0 | 0
Debt securities, available-for-sale, 12 months or longer, accumulated loss | (1) | (2)
Debt securities, available-for-sale, accumulated loss | $ (1) | $ (2)
Other debt securities |  |
Schedule Of Securities [Line Items] |  |
Debt securities, available-for-sale, less than 12 months, number of positions | security | 0 | 0
Debt securities, available-for-sale, 12 months or longer, number of positions | security | 3 | 4
Debt securities, available-for-sale, number of positions | security | 3 | 4
Debt securities, available-for-sale, less than 12 months | $ 0 | $ 0
Debt securities, available-for-sale, 12 months or longer | 9 | 10
Debt securities, available-for-sale, unrealized loss position | 9 | 10
Debt securities, available-for-sale, less than 12 months, accumulated loss | 0 | 0
Debt securities, available-for-sale, 12 months or longer, accumulated loss | 0 | 0
Debt securities, available-for-sale, accumulated loss | $ 0 | $ 0

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