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Securities, Held to Maturity (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Held-to-maturity securities, fair value to amortized cost [Abstract] |  |  |
Amortized cost | $ 842,921 | $ 905,267 |
Unrealized gains | 42 | 271 |
Unrealized losses | (93,018) | (91,014) |
Estimated fair value | 749,945 | 814,524 |
Transactions of HTM securities [Abstract] |  |  |
Gains from calls on HTM securities | 0 | 0 | $ 4
Asset Pledged as Collateral [Member] | Public Deposits and Other Purposes [Member] |  |  |
Securities pledged [Abstract] |  |  |
AFS and HTM securities | 1,600,000 | 2,030,000 |
Asset Pledged as Collateral [Member] | Securities Sold under Repurchase Agreements [Member] |  |  |
Securities pledged [Abstract] |  |  |
AFS and HTM securities | 234,200 | 177,200 |
Federal Agency [Member] |  |  |
Held-to-maturity securities, fair value to amortized cost [Abstract] |  |  |
Amortized cost | 100,000 | 100,000 |
Unrealized gains | 0 | 0 |
Unrealized losses | (16,656) | (17,784) |
Estimated fair value | 83,344 | 82,216 |
Mortgage-backed Securities, Government-Sponsored Enterprises [Member] |  |  |
Held-to-maturity securities, fair value to amortized cost [Abstract] |  |  |
Amortized cost | 208,579 | 228,720 |
Unrealized gains | 0 | 0 |
Unrealized losses | (34,349) | (31,613) |
Estimated fair value | 174,230 | 197,107 |
Mortgage-Backed, U.S. Government Agency Securities [Member] |  |  |
Held-to-maturity securities, fair value to amortized cost [Abstract] |  |  |
Amortized cost | 15,611 | 17,086 |
Unrealized gains | 1 | 3 |
Unrealized losses | (516) | (566) |
Estimated fair value | 15,096 | 16,523 |
Collateralized Mortgage Obligations, Government-Sponsored Enterprises [Member] |  |  |
Held-to-maturity securities, fair value to amortized cost [Abstract] |  |  |
Amortized cost | 168,018 | 187,457 |
Unrealized gains | 0 | 57 |
Unrealized losses | (11,554) | (12,021) |
Estimated fair value | 156,464 | 175,493 |
Collateralized Mortgage Obligations, U.S. Government Agency Securities [Member] |  |  |
Held-to-maturity securities, fair value to amortized cost [Abstract] |  |  |
Amortized cost | 60,906 | 63,878 |
Unrealized gains | 0 | 0 |
Unrealized losses | (11,245) | (10,908) |
Estimated fair value | 49,661 | 52,970 |
State & Municipal [Member] |  |  |
Held-to-maturity securities, fair value to amortized cost [Abstract] |  |  |
Amortized cost | 289,807 | 308,126 |
Unrealized gains | 41 | 211 |
Unrealized losses | (18,698) | (18,122) |
Estimated fair value | $ 271,150 | $ 290,215 |

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