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Securities, HTM Securities in Continuous Unrealized Loss Position (Details) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2024 USD ($) Position | Sep. 30, 2024 USD ($) Position | Dec. 31, 2023 USD ($) Position
Unrealized Loss Position, Fair Value [Abstract] |  |  |
Less than 12 months | $ 2,908 | $ 2,908 | $ 26,643
12 months or longer | 670,988 | 670,988 | 675,260
Total | 673,896 | 673,896 | 701,903
Unrealized Loss Position, Unrealized Losses [Abstract] |  |  |
Less than 12 months | (2) | (2) | (492)
12 months or longer | (73,326) | (73,326) | (90,522)
Total | $ (73,328) | $ (73,328) | $ (91,014)
Unrealized Loss Position, Number of Positions [Abstract] |  |  |
Less than 12 months | Position | 3 | 3 | 22
12 months or longer | Position | 277 | 277 | 280
Total | Position | 280 | 280 | 302
HTM debt securities, nonaccrual | $ 0 | $ 0 | $ 0
Accrued interest reversed against interest income | 0 | 0 | 0
Collateral-dependent HTM debt securities | 0 | 0 | 0
Allowance for credit losses on HTM securities | 0 | 0 | 0
AIR on HTM debt securities | $ 3,800 | $ 3,800 | $ 4,700
Debt Securities, Held-to-Maturity, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration] | Other Assets | Other Assets | Other Assets
Past Due [Member] |  |  |
Unrealized Loss Position, Number of Positions [Abstract] |  |  |
HTM debt securities | $ 0 | $ 0 | $ 0
Federal Agency [Member] |  |  |
Unrealized Loss Position, Fair Value [Abstract] |  |  |
Less than 12 months | 0 | 0 | 0
12 months or longer | 85,736 | 85,736 | 82,216
Total | 85,736 | 85,736 | 82,216
Unrealized Loss Position, Unrealized Losses [Abstract] |  |  |
Less than 12 months | 0 | 0 | 0
12 months or longer | (14,264) | (14,264) | (17,784)
Total | $ (14,264) | $ (14,264) | $ (17,784)
Unrealized Loss Position, Number of Positions [Abstract] |  |  |
Less than 12 months | Position | 0 | 0 | 0
12 months or longer | Position | 4 | 4 | 4
Total | Position | 4 | 4 | 4
Mortgage-Backed [Member] |  |  |
Unrealized Loss Position, Fair Value [Abstract] |  |  |
Less than 12 months | $ 0 | $ 0 | $ 12,221
12 months or longer | 202,256 | 202,256 | 201,320
Total | 202,256 | 202,256 | 213,541
Unrealized Loss Position, Unrealized Losses [Abstract] |  |  |
Less than 12 months | 0 | 0 | (365)
12 months or longer | (26,871) | (26,871) | (31,814)
Total | $ (26,871) | $ (26,871) | $ (32,179)
Unrealized Loss Position, Number of Positions [Abstract] |  |  |
Less than 12 months | Position | 0 | 0 | 1
12 months or longer | Position | 34 | 34 | 33
Total | Position | 34 | 34 | 34
Collateralized Mortgage Obligations [Member] |  |  |
Unrealized Loss Position, Fair Value [Abstract] |  |  |
Less than 12 months | $ 0 | $ 0 | $ 0
12 months or longer | 208,993 | 208,993 | 219,820
Total | 208,993 | 208,993 | 219,820
Unrealized Loss Position, Unrealized Losses [Abstract] |  |  |
Less than 12 months | 0 | 0 | 0
12 months or longer | (17,721) | (17,721) | (22,929)
Total | $ (17,721) | $ (17,721) | $ (22,929)
Unrealized Loss Position, Number of Positions [Abstract] |  |  |
Less than 12 months | Position | 0 | 0 | 0
12 months or longer | Position | 52 | 52 | 54
Total | Position | 52 | 52 | 54
State & Municipal [Member] |  |  |
Unrealized Loss Position, Fair Value [Abstract] |  |  |
Less than 12 months | $ 2,908 | $ 2,908 | $ 14,422
12 months or longer | 174,003 | 174,003 | 171,904
Total | 176,911 | 176,911 | 186,326
Unrealized Loss Position, Unrealized Losses [Abstract] |  |  |
Less than 12 months | (2) | (2) | (127)
12 months or longer | (14,470) | (14,470) | (17,995)
Total | $ (14,472) | $ (14,472) | $ (18,122)
Unrealized Loss Position, Number of Positions [Abstract] |  |  |
Less than 12 months | Position | 3 | 3 | 21
12 months or longer | Position | 187 | 187 | 189
Total | Position | 190 | 190 | 210
US Government Agencies Debt Securities and US Government-sponsored Enterprises Debt Securities [Member] |  |  |
Unrealized Loss Position, Number of Positions [Abstract] |  |  |
Held-to-maturity debt securities, percentage |  | 66.00% | 66.00%

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