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Securities - Contractual Maturity (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Amortized Cost |  |
Due within one year | $ 420 |
Due after one year through five years | 5,649 |
Due after five years through ten years | 180,726 |
Due after ten years | 93,741 |
Amortized Cost | 1,051,916 | $ 1,126,144
Fair Value |  |
Due within one year | 420 |
Due after one year through five years | 5,427 |
Due after five years through ten years | 161,444 |
Due after ten years | 79,686 |
Fair Value | 976,690 | 1,002,544
Amortized Cost |  |
Due within one year | 9,797 |
Due after one year through five years | 76,154 |
Due after five years through ten years | 121,374 |
Due after ten years | 119,660 |
Amortized Cost | 2,599,397 | 968,927
Fair Value |  |
Due within one year | 9,815 |
Due after one year through five years | 76,555 |
Due after five years through ten years | 121,260 |
Due after ten years | 121,614 |
Fair Value | 2,512,650 | 831,013
Residential mortgage backed securities: |  |
Amortized Cost |  |
Amortized Cost | 327,592 | 354,882
Fair Value |  |
Fair Value | 308,063 | 313,376
Other debt securities |  |
Amortized Cost |  |
Without single maturity date, amortized cost | 48,090 |
Amortized Cost | 48,090 | 53,683
Fair Value |  |
Without single maturity date, fair value | 45,650 |
Fair Value | 45,650 | 49,603
Amortized Cost |  |
Debt securities, without fixed maturity, amortized cost | 308,184 |
Amortized Cost | 364,473 | 130,175
Fair Value |  |
Debt securities, without fixed maturity, fair value | 306,510 |
Fair Value | 362,105 | 127,960
Mortgage backed securities issued by U.S. Government agencies or sponsored enterprises | Residential mortgage backed securities: |  |
Amortized Cost |  |
Without single maturity date, amortized cost | 336,382 |
Amortized Cost | 336,382 | 372,414
Fair Value |  |
Without single maturity date, fair value | 324,998 |
Fair Value | 324,998 | 347,163
Amortized Cost |  |
Debt securities, without fixed maturity, amortized cost | 710,105 |
Amortized Cost | 710,105 | 185,292
Fair Value |  |
Debt securities, without fixed maturity, fair value | 696,306 |
Fair Value | 696,306 | 160,905
Mortgage backed securities issued by U.S. Government agencies or sponsored enterprises | Commercial mortgage backed securities: |  |
Amortized Cost |  |
Without single maturity date, amortized cost | 16,944 |
Amortized Cost | 16,944 | 16,961
Fair Value |  |
Without single maturity date, fair value | 14,759 |
Fair Value | 14,759 | 14,003
Amortized Cost |  |
Debt securities, without fixed maturity, amortized cost | 100,337 |
Amortized Cost | 100,337 | 11,373
Fair Value |  |
Debt securities, without fixed maturity, fair value | 99,759 |
Fair Value | 99,759 | 10,622
Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises | Residential mortgage backed securities: |  |
Amortized Cost |  |
Without single maturity date, amortized cost | 327,592 |
Fair Value |  |
Without single maturity date, fair value | 308,063 |
Amortized Cost |  |
Debt securities, without fixed maturity, amortized cost | 739,005 |
Amortized Cost | 739,005 | 475,311
Fair Value |  |
Debt securities, without fixed maturity, fair value | 682,080 |
Fair Value | 682,080 | 388,516
Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises | Commercial mortgage backed securities: |  |
Amortized Cost |  |
Without single maturity date, amortized cost | 42,372 |
Amortized Cost | 42,372 | 43,662
Fair Value |  |
Without single maturity date, fair value | 36,243 |
Fair Value | 36,243 | 36,345
Amortized Cost |  |
Debt securities, without fixed maturity, amortized cost | 414,781 |
Amortized Cost | 414,781 | 146,510
Fair Value |  |
Debt securities, without fixed maturity, fair value | 398,751 |
Fair Value | $ 398,751 | $ 124,956

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