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Securities (Details) - USD ($) $ in Thousands | Sep. 30, 2024 | Dec. 31, 2023
--- | --- | ---
Debt Securities, Available-for-Sale [Line Items] |  |
Amortized Cost | $ 1,482,798 | $ 1,516,841
Gross Unrealized Gains | 5,564 | 5,424
Gross Unrealized Losses | (195,012) | (222,564)
Fair Value | 1,293,350 | 1,299,701
U.S. Treasury and U.S. government sponsored entities |  |
Debt Securities, Available-for-Sale [Line Items] |  |
Amortized Cost | 132,478 | 145,439
Gross Unrealized Gains | 119 | 113
Gross Unrealized Losses | (13,004) | (17,597)
Fair Value | 119,593 | 127,955
State and political subdivisions |  |
Debt Securities, Available-for-Sale [Line Items] |  |
Amortized Cost | 611,001 | 644,880
Gross Unrealized Gains | 4,159 | 4,792
Gross Unrealized Losses | (87,438) | (93,503)
Fair Value | 527,722 | 556,169
Corporate bonds |  |
Debt Securities, Available-for-Sale [Line Items] |  |
Amortized Cost | 18,494 | 18,554
Gross Unrealized Gains | 313 | 187
Gross Unrealized Losses | (371) | (466)
Fair Value | 18,436 | 18,275
Mortgage-backed securities - residential |  |
Debt Securities, Available-for-Sale [Line Items] |  |
Amortized Cost | 601,239 | 624,529
Gross Unrealized Gains | 491 | 1
Gross Unrealized Losses | (88,517) | (104,144)
Fair Value | 513,213 | 520,386
Collateralized mortgage obligations |  |
Debt Securities, Available-for-Sale [Line Items] |  |
Amortized Cost | 116,764 | 80,227
Gross Unrealized Gains | 482 | 331
Gross Unrealized Losses | (5,485) | (6,559)
Fair Value | 111,761 | 73,999
Small Business Administration |  |
Debt Securities, Available-for-Sale [Line Items] |  |
Amortized Cost | 2,822 | 3,212
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (197) | (295)
Fair Value | $ 2,625 | $ 2,917

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