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Securities - Amortized Cost and Estimated Fair Value of Securities (Details) - USD ($) $ in Thousands | Jun. 30, 2024 | Dec. 31, 2023 | Jun. 30, 2023 | Dec. 31, 2022
--- | --- | --- | --- | ---
Available for sale: |  |  |  |
Amortized Cost | $ 1,321,942 | $ 1,407,675 |  |
Gross Unrealized Gains | 533 | 297 |  |
Gross Unrealized Losses | (162,427) | (154,341) |  |
Fair Value | 1,160,048 | 1,253,631 |  |
Allowance for Credit Losses | 0 | 0 |  |
Net Carrying Amount | 1,160,048 | 1,253,631 |  |
Held to maturity: |  |  |  |
Amortized Cost | 11,673 |  |  |
Fair Value | 10,876 | 10,848 |  |
Allowance for Credit Losses | (57) | (63) | $ (935) | $ (899)
Net Carrying Amount | 11,616 | 11,615 |  |
Securities carried at fair value through income: |  |  |  |
Fair Value | 6,499 | 6,808 |  |
State and municipal securities |  |  |  |
Available for sale: |  |  |  |
Amortized Cost | 320,357 | 323,356 |  |
Gross Unrealized Gains | 159 | 210 |  |
Gross Unrealized Losses | (46,106) | (41,440) |  |
Fair Value | 274,410 | 282,126 |  |
Allowance for Credit Losses | 0 | 0 |  |
Net Carrying Amount | 274,410 | 282,126 |  |
Held to maturity: |  |  |  |
Amortized Cost | 11,673 | 11,678 |  |
Gross Unrealized Gains | 0 | 0 |  |
Gross Unrealized Losses | (797) | (830) |  |
Fair Value | 10,876 | 10,848 |  |
Allowance for Credit Losses | (57) | (63) |  |
Net Carrying Amount | 11,616 | 11,615 |  |
Securities carried at fair value through income: |  |  |  |
Amortized Cost | 6,515 | 6,815 |  |
Fair Value | 6,499 | 6,808 |  |
Net Carrying Amount | 6,499 | 6,808 |  |
Corporate bonds |  |  |  |
Available for sale: |  |  |  |
Amortized Cost | 102,794 | 92,244 |  |
Gross Unrealized Gains | 338 | 80 |  |
Gross Unrealized Losses | (8,510) | (8,689) |  |
Fair Value | 94,622 | 83,635 |  |
Allowance for Credit Losses | 0 | 0 |  |
Net Carrying Amount | 94,622 | 83,635 |  |
U.S. treasury and government agency securities |  |  |  |
Available for sale: |  |  |  |
Amortized Cost | 49,110 | 84,377 |  |
Gross Unrealized Gains | 7 | 3 |  |
Gross Unrealized Losses | (4,564) | (4,740) |  |
Fair Value | 44,553 | 79,640 |  |
Allowance for Credit Losses | 0 | 0 |  |
Net Carrying Amount | 44,553 | 79,640 |  |
Commercial mortgage-backed securities |  |  |  |
Available for sale: |  |  |  |
Amortized Cost | 103,845 | 104,459 |  |
Gross Unrealized Gains | 0 | 0 |  |
Gross Unrealized Losses | (10,950) | (11,063) |  |
Fair Value | 92,895 | 93,396 |  |
Allowance for Credit Losses | 0 | 0 |  |
Net Carrying Amount | 92,895 | 93,396 |  |
Residential mortgage-backed securities |  |  |  |
Available for sale: |  |  |  |
Amortized Cost | 534,062 | 569,622 |  |
Gross Unrealized Gains | 0 | 0 |  |
Gross Unrealized Losses | (66,436) | (63,120) |  |
Fair Value | 467,626 | 506,502 |  |
Allowance for Credit Losses | 0 | 0 |  |
Net Carrying Amount | 467,626 | 506,502 |  |
Commercial collateralized mortgage obligations |  |  |  |
Available for sale: |  |  |  |
Amortized Cost | 49,077 | 39,386 |  |
Gross Unrealized Gains | 0 | 0 |  |
Gross Unrealized Losses | (4,442) | (4,203) |  |
Fair Value | 44,635 | 35,183 |  |
Allowance for Credit Losses | 0 | 0 |  |
Net Carrying Amount | 44,635 | 35,183 |  |
Residential collateralized mortgage obligations |  |  |  |
Available for sale: |  |  |  |
Amortized Cost | 143,438 | 150,710 |  |
Gross Unrealized Gains | 0 | 0 |  |
Gross Unrealized Losses | (21,382) | (20,566) |  |
Fair Value | 122,056 | 130,144 |  |
Allowance for Credit Losses | 0 | 0 |  |
Net Carrying Amount | 122,056 | 130,144 |  |
Asset-backed securities |  |  |  |
Available for sale: |  |  |  |
Amortized Cost | 19,259 | 43,521 |  |
Gross Unrealized Gains | 29 | 4 |  |
Gross Unrealized Losses | (37) | (520) |  |
Fair Value | 19,251 | 43,005 |  |
Allowance for Credit Losses | 0 | 0 |  |
Net Carrying Amount | $ 19,251 | $ 43,005 |  |

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