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AFS Securities (Amortized cost and fair value of AFS securities by contractual maturity) (Details) - USD ($) $ in Thousands | Jun. 30, 2024 | Dec. 31, 2023
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Debt Securities, Available-for-sale, Maturity, Amortized Cost, Rolling Maturity [Abstract] |  |
Maturing, Due in One Year or Less | $ 35,535 |
Maturing, After One Year But Within Five Years | 235,344 |
Maturing, After Five Years But Within Ten Years | 26,592 |
Maturing, After Ten Years | 28,480 |
Securities With Variable Monthly Payments or Noncontractual Maturities | 213,744 |
Amortized Cost | 539,695 | $ 559,974
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract] |  |
Maturing, Due in One Year or Less, Fair value | 35,351 |
Maturing, After One Year But Within Five Years, Fair value | 219,602 |
Maturing, After Five Years But Within Ten Years, Fair value | 24,268 |
Maturing, After Ten Years, Fair value | 26,167 |
Securities With Variable Monthly Payments or Noncontractual Maturities, Fair value | 200,258 |
Total, Fair value | 505,646 | 528,148
US Treasury Securities |  |
Debt Securities, Available-for-sale, Maturity, Amortized Cost, Rolling Maturity [Abstract] |  |
Maturing, Due in One Year or Less | 19,922 |
Maturing, After One Year But Within Five Years | 211,090 |
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 | 231,012 | 231,218
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract] |  |
Total, Fair value | 215,333 | 214,801
States and political subdivisions [Member] |  |
Debt Securities, Available-for-sale, Maturity, Amortized Cost, Rolling Maturity [Abstract] |  |
Maturing, Due in One Year or Less | 15,613 |
Maturing, After One Year But Within Five Years | 24,254 |
Maturing, After Five Years But Within Ten Years | 18,442 |
Maturing, After Ten Years | 28,480 |
Securities With Variable Monthly Payments or Noncontractual Maturities | 0 |
Amortized Cost | 86,789 | 94,837
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract] |  |
Total, Fair value | 83,051 | 92,876
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 | 3,008 | 2,931
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 | 32,120 |
Amortized Cost | 32,120 | 35,321
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract] |  |
Total, Fair value | 29,541 | 32,815
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 | 178,424 |
Amortized Cost | 178,424 | 187,248
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract] |  |
Total, Fair value | 167,709 | 177,775
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 | $ 7,004 | $ 6,950

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