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Investment Securities - Schedule of Available-for-sale Investment Securities Portfolios (Details) - USD ($) | Dec. 31, 2025 | Dec. 31, 2024
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Available-for-sale securities |  |
Continuous unrealized losses existing for less than 12 months, fair value | $ 723,180,000 | $ 2,460,239,000
Continuous unrealized losses existing for less than 12 months, unrealized losses | (10,662,000) | (550,821,000)
Continuous unrealized losses existing for greater than 12 months, fair value | 2,376,825,000 | 1,430,683,000
Continuous unrealized losses existing for greater than 12 months, unrealized losses | (419,036,000) | (35,307,000)
Total, fair value | 3,100,005,000 | 3,890,922,000
Total, unrealized losses | (429,698,000) | (586,128,000)
Available-for-sale securities | 6,236,263,000 | 4,141,482,000
U.S. government agencies |  |
Available-for-sale securities |  |
Continuous unrealized losses existing for less than 12 months, fair value | 0 | 44,945,000
Continuous unrealized losses existing for less than 12 months, unrealized losses | 0 | (5,055,000)
Continuous unrealized losses existing for greater than 12 months, fair value | 47,471,000 | 0
Continuous unrealized losses existing for greater than 12 months, unrealized losses | (2,529,000) | 0
Total, fair value | 47,471,000 | 44,945,000
Total, unrealized losses | (2,529,000) | (5,055,000)
Available-for-sale securities | 47,471,000 | 44,945,000
Municipal |  |
Available-for-sale securities |  |
Continuous unrealized losses existing for less than 12 months, fair value | 36,516,000 | 52,344,000
Continuous unrealized losses existing for less than 12 months, unrealized losses | (142,000) | (3,536,000)
Continuous unrealized losses existing for greater than 12 months, fair value | 37,288,000 | 83,517,000
Continuous unrealized losses existing for greater than 12 months, unrealized losses | (1,708,000) | (804,000)
Total, fair value | 73,804,000 | 135,861,000
Total, unrealized losses | (1,850,000) | (4,340,000)
Available-for-sale securities | 162,166,000 | 184,593,000
Financial issuers |  |
Available-for-sale securities |  |
Continuous unrealized losses existing for less than 12 months, fair value | 0 | 80,169,000
Continuous unrealized losses existing for less than 12 months, unrealized losses | 0 | (3,828,000)
Continuous unrealized losses existing for greater than 12 months, fair value | 76,296,000 | 0
Continuous unrealized losses existing for greater than 12 months, unrealized losses | (2,704,000) | 0
Total, fair value | 76,296,000 | 80,169,000
Total, unrealized losses | (2,704,000) | (3,828,000)
Available-for-sale securities | 76,296,000 | 80,169,000
Other |  |
Available-for-sale securities |  |
Continuous unrealized losses existing for less than 12 months, fair value | 999,000 | 993,000
Continuous unrealized losses existing for less than 12 months, unrealized losses | (1,000) | (7,000)
Continuous unrealized losses existing for greater than 12 months, fair value | 0 | 0
Continuous unrealized losses existing for greater than 12 months, unrealized losses | 0 | 0
Total, fair value | 999,000 | 993,000
Total, unrealized losses | (1,000) | (7,000)
Available-for-sale securities | 999,000 | 993,000
Residential mortgage-backed securities |  |
Available-for-sale securities |  |
Continuous unrealized losses existing for less than 12 months, fair value | 378,503,000 | 2,212,780,000
Continuous unrealized losses existing for less than 12 months, unrealized losses | (5,976,000) | (519,164,000)
Continuous unrealized losses existing for greater than 12 months, fair value | 2,145,980,000 | 1,327,534,000
Continuous unrealized losses existing for greater than 12 months, unrealized losses | (396,977,000) | (34,123,000)
Total, fair value | 2,524,483,000 | 3,540,314,000
Total, unrealized losses | (402,953,000) | (553,287,000)
Available-for-sale securities | 5,156,683,000 | 3,553,638,000
Commercial (multi-family) mortgage-baked securities |  |
Available-for-sale securities |  |
Continuous unrealized losses existing for less than 12 months, fair value | 215,561,000 | 3,134,000
Continuous unrealized losses existing for less than 12 months, unrealized losses | (4,420,000) | (390,000)
Continuous unrealized losses existing for greater than 12 months, fair value | 6,094,000 | 12,204,000
Continuous unrealized losses existing for greater than 12 months, unrealized losses | (566,000) | (365,000)
Total, fair value | 221,655,000 | 15,338,000
Total, unrealized losses | (4,986,000) | (755,000)
Available-for-sale securities | 276,553,000 | 18,332,000
Collateralized mortgage obligations |  |
Available-for-sale securities |  |
Continuous unrealized losses existing for less than 12 months, fair value | 91,601,000 | 65,874,000
Continuous unrealized losses existing for less than 12 months, unrealized losses | (123,000) | (18,841,000)
Continuous unrealized losses existing for greater than 12 months, fair value | 63,696,000 | 7,428,000
Continuous unrealized losses existing for greater than 12 months, unrealized losses | (14,552,000) | (15,000)
Total, fair value | 155,297,000 | 73,302,000
Total, unrealized losses | (14,675,000) | (18,856,000)
Available-for-sale securities | 509,060,000 | 220,905,000
Mortgage Backed Securities, Subprime |  |
Available-for-sale securities |  |
Available-for-sale securities | $ 0 | $ 0

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