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Securities - Amortized Cost and Fair Value of Debt Securities (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | $ 1,038,627 | $ 1,058,154
Gross Unrealized Gains | 7,257 | 990
Gross Unrealized Losses | (46,054) | (72,729)
Fair Value | 999,830 | 986,415
Interest receivable | 3,300 | 3,700
U.S. Treasury securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 96,544 | 97,045
Gross Unrealized Gains | 103 | 0
Gross Unrealized Losses | (2,385) | (4,277)
Fair Value | 94,262 | 92,768
Obligations of U.S. government corporations and agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 0 | 15,260
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 0 | (189)
Fair Value | 0 | 15,071
Collateralized mortgage obligations of U.S. government corporations and agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 665,945 | 643,690
Gross Unrealized Gains | 4,756 | 872
Gross Unrealized Losses | (33,165) | (48,278)
Fair Value | 637,536 | 596,284
Residential mortgage-backed securities of U.S. government corporations and agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 36,950 | 40,109
Gross Unrealized Gains | 7 | 3
Gross Unrealized Losses | (5,101) | (6,905)
Fair Value | 31,856 | 33,207
Commercial mortgage-backed securities of U.S. government corporations and agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 234,259 | 237,270
Gross Unrealized Gains | 2,377 | 115
Gross Unrealized Losses | (5,403) | (12,587)
Fair Value | 231,233 | 224,798
Obligations of states and political subdivisions |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 4,929 | 24,780
Gross Unrealized Gains | 14 | 0
Gross Unrealized Losses | 0 | (493)
Fair Value | $ 4,943 | $ 24,287

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