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AFS Securities - Amortized Cost and Fair Value of AFS Securities by Contractual Maturity (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
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Debt Securities, Available-for-sale, Maturity, Amortized Cost, Rolling Maturity [Abstract] |  |
Due in One Year or Less | $ 173,213 |
After One Year But Within Five Years | 68,504 |
After Five Years But Within Ten Years | 28,198 |
After Ten Years | 22,739 |
Securities with Variable Monthly Payments or Noncontractual Maturities | 231,880 |
Total | 524,534 | $ 515,516
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract] |  |
Due in One Year or Less | 170,246 |
After One Year But Within Five Years | 66,903 |
After Five Years But Within Ten Years | 26,153 |
After Ten Years | 21,268 |
Securities with Variable Monthly Payments or Noncontractual Maturities | 227,400 |
Total | 511,970 | 489,029
U.S. Treasury |  |
Debt Securities, Available-for-sale, Maturity, Amortized Cost, Rolling Maturity [Abstract] |  |
Due in One Year or Less | 160,417 |
After One Year But Within Five Years | 50,045 |
After Five Years But Within Ten Years | 0 |
After Ten Years | 0 |
Securities with Variable Monthly Payments or Noncontractual Maturities | 0 |
Total | 210,462 | 230,807
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract] |  |
Total | 206,041 | 220,571
States and political subdivisions |  |
Debt Securities, Available-for-sale, Maturity, Amortized Cost, Rolling Maturity [Abstract] |  |
Due in One Year or Less | 12,796 |
After One Year But Within Five Years | 18,459 |
After Five Years But Within Ten Years | 20,048 |
After Ten Years | 22,739 |
Securities with Variable Monthly Payments or Noncontractual Maturities | 0 |
Total | 74,042 | 81,135
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract] |  |
Total | 71,102 | 76,568
Auction Rate Money Market Preferred |  |
Debt Securities, Available-for-sale, Maturity, Amortized Cost, Rolling Maturity [Abstract] |  |
Due in One Year or Less | 0 |
After One Year But Within Five Years | 0 |
After Five Years But Within Ten Years | 0 |
After Ten Years | 0 |
Securities with Variable Monthly Payments or Noncontractual Maturities | 3,200 |
Total | 3,200 | 3,200
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract] |  |
Total | 2,790 | 3,044
Mortgage-backed securities |  |
Debt Securities, Available-for-sale, Maturity, Amortized Cost, Rolling Maturity [Abstract] |  |
Due in One Year or Less | 0 |
After One Year But Within Five Years | 0 |
After Five Years But Within Ten Years | 0 |
After Ten Years | 0 |
Securities with Variable Monthly Payments or Noncontractual Maturities | 24,696 |
Total | 24,696 | 29,068
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract] |  |
Total | 23,397 | 26,886
Collateralized mortgage obligations |  |
Debt Securities, Available-for-sale, Maturity, Amortized Cost, Rolling Maturity [Abstract] |  |
Due in One Year or Less | 0 |
After One Year But Within Five Years | 0 |
After Five Years But Within Ten Years | 0 |
After Ten Years | 0 |
Securities with Variable Monthly Payments or Noncontractual Maturities | 203,984 |
Total | 203,984 | 163,156
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract] |  |
Total | 201,213 | 154,674
Corporate |  |
Debt Securities, Available-for-sale, Maturity, Amortized Cost, Rolling Maturity [Abstract] |  |
Due in One Year or Less | 0 |
After One Year But Within Five Years | 0 |
After Five Years But Within Ten Years | 8,150 |
After Ten Years | 0 |
Securities with Variable Monthly Payments or Noncontractual Maturities | 0 |
Total | 8,150 | 8,150
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract] |  |
Total | $ 7,427 | $ 7,286

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