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AFS Securities (Amortized cost and fair value of AFS securities by contractual maturity) (Details) - USD ($) $ in Thousands | Jun. 30, 2025 | Dec. 31, 2024
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Debt Securities, Available-for-sale, Maturity, Amortized Cost, Rolling Maturity [Abstract] |  |
Maturing, Due in One Year or Less | $ 121,716 |
Maturing, After One Year But Within Five Years | 118,884 |
Maturing, After Five Years But Within Ten Years | 28,203 |
Maturing, After Ten Years | 22,868 |
Securities With Variable Monthly Payments or Noncontractual Maturities | 226,483 |
Amortized Cost | 518,154 | $ 515,516
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract] |  |
Maturing, Due in One Year or Less, Fair value | 118,985 |
Maturing, After One Year But Within Five Years, Fair value | 115,038 |
Maturing, After Five Years But Within Ten Years, Fair value | 25,551 |
Maturing, After Ten Years, Fair value | 20,324 |
Securities With Variable Monthly Payments or Noncontractual Maturities, Fair value | 220,662 |
Total, Fair value | 500,560 | 489,029
US Treasury Securities |  |
Debt Securities, Available-for-sale, Maturity, Amortized Cost, Rolling Maturity [Abstract] |  |
Maturing, Due in One Year or Less | 110,318 |
Maturing, After One Year But Within Five Years | 100,270 |
Maturing, After Five Years But Within Ten Years | 0 |
Maturing, After Ten Years | 0 |
Securities With Variable Monthly Payments or Noncontractual Maturities | 0 |
Amortized Cost | 210,588 | 230,807
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract] |  |
Total, Fair value | 204,306 | 220,571
States and political subdivisions [Member] |  |
Debt Securities, Available-for-sale, Maturity, Amortized Cost, Rolling Maturity [Abstract] |  |
Maturing, Due in One Year or Less | 11,398 |
Maturing, After One Year But Within Five Years | 18,614 |
Maturing, After Five Years But Within Ten Years | 20,053 |
Maturing, After Ten Years | 22,868 |
Securities With Variable Monthly Payments or Noncontractual Maturities | 0 |
Amortized Cost | 72,933 | 81,135
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract] |  |
Total, Fair value | 68,320 | 76,568
Auction Rate Securities [Member] |  |
Debt Securities, Available-for-sale, Maturity, Amortized Cost, Rolling Maturity [Abstract] |  |
Maturing, Due in One Year or Less | 0 |
Maturing, After One Year But Within Five Years | 0 |
Maturing, After Five Years But Within Ten Years | 0 |
Maturing, After Ten Years | 0 |
Securities With Variable Monthly Payments or Noncontractual Maturities | 3,200 |
Amortized Cost | 3,200 | 3,200
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract] |  |
Total, Fair value | 2,765 | 3,044
Mortgage-backed securities [Member] |  |
Debt Securities, Available-for-sale, Maturity, Amortized Cost, Rolling Maturity [Abstract] |  |
Maturing, Due in One Year or Less | 0 |
Maturing, After One Year But Within Five Years | 0 |
Maturing, After Five Years But Within Ten Years | 0 |
Maturing, After Ten Years | 0 |
Securities With Variable Monthly Payments or Noncontractual Maturities | 26,093 |
Amortized Cost | 26,093 | 29,068
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract] |  |
Total, Fair value | 24,657 | 26,886
Collateralized mortgage obligations [Member] |  |
Debt Securities, Available-for-sale, Maturity, Amortized Cost, Rolling Maturity [Abstract] |  |
Maturing, Due in One Year or Less | 0 |
Maturing, After One Year But Within Five Years | 0 |
Maturing, After Five Years But Within Ten Years | 0 |
Maturing, After Ten Years | 0 |
Securities With Variable Monthly Payments or Noncontractual Maturities | 197,190 |
Amortized Cost | 197,190 | 163,156
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract] |  |
Total, Fair value | 193,240 | 154,674
Corporate Debt Securities |  |
Debt Securities, Available-for-sale, Maturity, Amortized Cost, Rolling Maturity [Abstract] |  |
Maturing, Due in One Year or Less | 0 |
Maturing, After One Year But Within Five Years | 0 |
Maturing, After Five Years But Within Ten Years | 8,150 |
Maturing, After Ten Years | 0 |
Securities With Variable Monthly Payments or Noncontractual Maturities | 0 |
Amortized Cost | 8,150 | 8,150
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract] |  |
Total, Fair value | $ 7,272 | $ 7,286

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