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Fair Value (Recorded amount of assets and liabilities measured at fair value) (Details) - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
AFS Securities |  |
Debt Securities, Available-for-sale | $ 528,148 | $ 580,481
Fair value, total | 529,637 | 598,063
Level 1 [Member] |  |
AFS Securities |  |
Fair value, total | $ 0 | $ 0
Percent of assets and liabilities measured at fair value | 0.00% | 0.00%
Level 2 [Member] |  |
AFS Securities |  |
Fair value, total | $ 528,148 | $ 580,481
Percent of assets and liabilities measured at fair value | 99.72% | 97.06%
Level 3 [Member] |  |
AFS Securities |  |
Fair value, total | $ 1,489 | $ 17,582
Percent of assets and liabilities measured at fair value | 0.28% | 2.94%
Recurring items [Member] |  |
AFS Securities |  |
Debt Securities, Available-for-sale | $ 528,148 | $ 580,481
Recurring items [Member] | US Treasury Securities |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 214,801 | 208,701
Recurring items [Member] | States and political subdivisions [Member] |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 92,876 | 117,512
Recurring items [Member] | Auction rate money market preferred [Member] |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 2,931 | 2,342
Recurring items [Member] | Mortgage-backed securities [Member] |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 32,815 | 39,070
Recurring items [Member] | Collateralized mortgage obligations [Member] |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 177,775 | 205,728
Recurring items [Member] | Corporate Debt Securities |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 6,950 | 7,128
Recurring items [Member] | Level 1 [Member] |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 0 | 0
Recurring items [Member] | Level 1 [Member] | US Treasury Securities |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 0 | 0
Recurring items [Member] | Level 1 [Member] | States and political subdivisions [Member] |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 0 | 0
Recurring items [Member] | Level 1 [Member] | Auction rate money market preferred [Member] |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 0 | 0
Recurring items [Member] | Level 1 [Member] | Mortgage-backed securities [Member] |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 0 | 0
Recurring items [Member] | Level 1 [Member] | Collateralized mortgage obligations [Member] |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 0 | 0
Recurring items [Member] | Level 1 [Member] | Corporate Debt Securities |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 0 | 0
Recurring items [Member] | Level 2 [Member] |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 528,148 | 580,481
Recurring items [Member] | Level 2 [Member] | US Treasury Securities |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 214,801 | 208,701
Recurring items [Member] | Level 2 [Member] | States and political subdivisions [Member] |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 92,876 | 117,512
Recurring items [Member] | Level 2 [Member] | Auction rate money market preferred [Member] |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 2,931 | 2,342
Recurring items [Member] | Level 2 [Member] | Mortgage-backed securities [Member] |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 32,815 | 39,070
Recurring items [Member] | Level 2 [Member] | Collateralized mortgage obligations [Member] |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 177,775 | 205,728
Recurring items [Member] | Level 2 [Member] | Corporate Debt Securities |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 6,950 | 7,128
Recurring items [Member] | Level 3 [Member] |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 0 | 0
Recurring items [Member] | Level 3 [Member] | US Treasury Securities |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 0 | 0
Recurring items [Member] | Level 3 [Member] | States and political subdivisions [Member] |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 0 | 0
Recurring items [Member] | Level 3 [Member] | Auction rate money market preferred [Member] |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 0 | 0
Recurring items [Member] | Level 3 [Member] | Mortgage-backed securities [Member] |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 0 | 0
Recurring items [Member] | Level 3 [Member] | Collateralized mortgage obligations [Member] |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 0 | 0
Recurring items [Member] | Level 3 [Member] | Corporate Debt Securities |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 0 | 0
Nonrecurring items [Member] |  |
AFS Securities |  |
Impaired loans (net of the allowance for loan losses) | 1,083 | 17,143
Foreclosed assets | 406 | 439
Nonrecurring items [Member] | Level 1 [Member] |  |
AFS Securities |  |
Impaired loans (net of the allowance for loan losses) | 0 | 0
Foreclosed assets | 0 | 0
Nonrecurring items [Member] | Level 2 [Member] |  |
AFS Securities |  |
Impaired loans (net of the allowance for loan losses) | 0 | 0
Foreclosed assets | 0 | 0
Nonrecurring items [Member] | Level 3 [Member] |  |
AFS Securities |  |
Impaired loans (net of the allowance for loan losses) | 1,083 | 17,143
Foreclosed assets | $ 406 | $ 439

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