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Investment Securities - Schedule of Investment Securities (Details) - USD ($) | Dec. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Available-for-sale securities |  |
Amortized Cost | $ 6,635,481,000 | $ 4,725,539,000
Gross unrealized gains | 30,480,000 | 2,071,000
Gross unrealized losses | (429,698,000) | (586,128,000)
Fair Value | 6,236,263,000 | 4,141,482,000
Held-to-maturity securities |  |
Amortized Cost | 3,344,165,000 | 3,613,720,000
Gross unrealized gains | 8,864,000 | 1,066,000
Gross unrealized losses | (567,882,000) | (704,236,000)
Held-to-maturity securities, fair value | 2,785,147,000 | 2,910,550,000
Less: Allowance for credit losses | (260,000) | (457,000)
Held-to-maturity securities, net of allowance for credit losses | 3,343,905,000 | 3,613,263,000
Equity securities with readily determinable fair value |  |
Amortized Cost | 61,211,000 | 220,758,000
Gross unrealized gains | 6,318,000 | 2,905,000
Gross unrealized losses | (3,759,000) | (8,251,000)
Fair Value | 63,770,000 | 215,412,000
U.S. Treasury |  |
Available-for-sale securities |  |
Amortized Cost | 6,999,000 | 37,858,000
Gross unrealized gains | 36,000 | 49,000
Gross unrealized losses | 0 | 0
Fair Value | 7,035,000 | 37,907,000
U.S. government agencies |  |
Available-for-sale securities |  |
Amortized Cost | 50,000,000 | 50,000,000
Gross unrealized gains | 0 | 0
Gross unrealized losses | (2,529,000) | (5,055,000)
Fair Value | 47,471,000 | 44,945,000
Held-to-maturity securities |  |
Amortized Cost | 313,541,000 | 313,539,000
Gross unrealized gains | 0 | 0
Gross unrealized losses | (57,269,000) | (69,127,000)
Held-to-maturity securities, fair value | 256,272,000 | 244,412,000
Municipal |  |
Available-for-sale securities |  |
Amortized Cost | 162,373,000 | 188,405,000
Gross unrealized gains | 1,643,000 | 528,000
Gross unrealized losses | (1,850,000) | (4,340,000)
Fair Value | 162,166,000 | 184,593,000
Held-to-maturity securities |  |
Amortized Cost | 144,192,000 | 161,016,000
Gross unrealized gains | 451,000 | 243,000
Gross unrealized losses | (2,012,000) | (5,290,000)
Held-to-maturity securities, fair value | 142,631,000 | 155,969,000
Corporate notes |  |
Held-to-maturity securities |  |
Amortized Cost | 35,097,000 | 56,851,000
Gross unrealized gains | 2,000 | 8,000
Gross unrealized losses | (396,000) | (1,870,000)
Held-to-maturity securities, fair value | 34,703,000 | 54,989,000
Financial issuers |  |
Available-for-sale securities |  |
Amortized Cost | 79,000,000 | 83,997,000
Gross unrealized gains | 0 | 0
Gross unrealized losses | (2,704,000) | (3,828,000)
Fair Value | 76,296,000 | 80,169,000
Other |  |
Available-for-sale securities |  |
Amortized Cost | 1,000,000 | 1,000,000
Gross unrealized gains | 0 | 0
Gross unrealized losses | (1,000) | (7,000)
Fair Value | 999,000 | 993,000
Residential mortgage-backed securities |  |
Available-for-sale securities |  |
Amortized Cost | 5,533,710,000 | 4,106,641,000
Gross unrealized gains | 25,926,000 | 284,000
Gross unrealized losses | (402,953,000) | (553,287,000)
Fair Value | 5,156,683,000 | 3,553,638,000
Held-to-maturity securities |  |
Amortized Cost | 2,667,371,000 | 2,864,927,000
Gross unrealized gains | 7,503,000 | 0
Gross unrealized losses | (491,124,000) | (605,014,000)
Held-to-maturity securities, fair value | 2,183,750,000 | 2,259,913,000
Commercial (multi-family) mortgage-baked securities |  |
Available-for-sale securities |  |
Amortized Cost | 280,969,000 | 19,064,000
Gross unrealized gains | 570,000 | 23,000
Gross unrealized losses | (4,986,000) | (755,000)
Fair Value | 276,553,000 | 18,332,000
Held-to-maturity securities |  |
Amortized Cost | 6,293,000 | 6,364,000
Gross unrealized gains | 72,000 | 0
Gross unrealized losses | (92,000) | (252,000)
Held-to-maturity securities, fair value | 6,273,000 | 6,112,000
Collateralized mortgage obligations |  |
Available-for-sale securities |  |
Amortized Cost | 521,430,000 | 238,574,000
Gross unrealized gains | 2,305,000 | 1,187,000
Gross unrealized losses | (14,675,000) | (18,856,000)
Fair Value | 509,060,000 | 220,905,000
Held-to-maturity securities |  |
Amortized Cost | 177,671,000 | 211,023,000
Gross unrealized gains | 836,000 | 815,000
Gross unrealized losses | (16,989,000) | (22,683,000)
Held-to-maturity securities, fair value | 161,518,000 | 189,155,000
Mortgage-backed securities, subprime |  |
Available-for-sale securities |  |
Fair Value | $ 0 | $ 0

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