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Fair Value (Recorded amount of assets and liabilities measured at fair value) (Details) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022
--- | --- | ---
AFS Securities |  |
AFS securities | $ 516,897 | $ 580,481
Fair value, total | 517,797 | 598,063
US Treasury Securities |  |
AFS Securities |  |
AFS securities | 209,182 | 208,701
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 | $ 516,897 | $ 580,481
Percent of assets and liabilities measured at fair value | 99.83% | 97.06%
Level 3 [Member] |  |
AFS Securities |  |
Fair value, total | $ 900 | $ 17,582
Percent of assets and liabilities measured at fair value | 0.17% | 2.94%
Recurring items [Member] |  |
AFS Securities |  |
AFS securities | $ 516,897 | $ 580,481
Recurring items [Member] | States and political subdivisions [Member] |  |
AFS Securities |  |
AFS securities | 89,773 | 117,512
Recurring items [Member] | Auction rate money market preferred [Member] |  |
AFS Securities |  |
AFS securities | 2,570 | 2,342
Recurring items [Member] | Mortgage-backed securities [Member] |  |
AFS Securities |  |
AFS securities | 32,923 | 39,070
Recurring items [Member] | Collateralized mortgage obligations [Member] |  |
AFS Securities |  |
AFS securities | 175,630 | 205,728
Recurring items [Member] | Corporate Debt Securities |  |
AFS Securities |  |
AFS securities | 6,819 | 7,128
Recurring items [Member] | US Treasury Securities |  |
AFS Securities |  |
AFS securities | 209,182 | 208,701
Recurring items [Member] | Level 1 [Member] |  |
AFS Securities |  |
AFS securities | 0 | 0
Recurring items [Member] | Level 1 [Member] | States and political subdivisions [Member] |  |
AFS Securities |  |
AFS securities | 0 | 0
Recurring items [Member] | Level 1 [Member] | Auction rate money market preferred [Member] |  |
AFS Securities |  |
AFS securities | 0 | 0
Recurring items [Member] | Level 1 [Member] | Mortgage-backed securities [Member] |  |
AFS Securities |  |
AFS securities | 0 | 0
Recurring items [Member] | Level 1 [Member] | Collateralized mortgage obligations [Member] |  |
AFS Securities |  |
AFS securities | 0 | 0
Recurring items [Member] | Level 1 [Member] | Corporate Debt Securities |  |
AFS Securities |  |
AFS securities | 0 | 0
Recurring items [Member] | Level 1 [Member] | US Treasury Securities |  |
AFS Securities |  |
AFS securities | 0 | 0
Recurring items [Member] | Level 2 [Member] |  |
AFS Securities |  |
AFS securities | 516,897 | 580,481
Recurring items [Member] | Level 2 [Member] | States and political subdivisions [Member] |  |
AFS Securities |  |
AFS securities | 89,773 | 117,512
Recurring items [Member] | Level 2 [Member] | Auction rate money market preferred [Member] |  |
AFS Securities |  |
AFS securities | 2,570 | 2,342
Recurring items [Member] | Level 2 [Member] | Mortgage-backed securities [Member] |  |
AFS Securities |  |
AFS securities | 32,923 | 39,070
Recurring items [Member] | Level 2 [Member] | Collateralized mortgage obligations [Member] |  |
AFS Securities |  |
AFS securities | 175,630 | 205,728
Recurring items [Member] | Level 2 [Member] | Corporate Debt Securities |  |
AFS Securities |  |
AFS securities | 6,819 | 7,128
Recurring items [Member] | Level 2 [Member] | US Treasury Securities |  |
AFS Securities |  |
AFS securities | 209,182 | 208,701
Recurring items [Member] | Level 3 [Member] |  |
AFS Securities |  |
AFS securities | 0 | 0
Recurring items [Member] | Level 3 [Member] | States and political subdivisions [Member] |  |
AFS Securities |  |
AFS securities | 0 | 0
Recurring items [Member] | Level 3 [Member] | Auction rate money market preferred [Member] |  |
AFS Securities |  |
AFS securities | 0 | 0
Recurring items [Member] | Level 3 [Member] | Mortgage-backed securities [Member] |  |
AFS Securities |  |
AFS securities | 0 | 0
Recurring items [Member] | Level 3 [Member] | Collateralized mortgage obligations [Member] |  |
AFS Securities |  |
AFS securities | 0 | 0
Recurring items [Member] | Level 3 [Member] | Corporate Debt Securities |  |
AFS Securities |  |
AFS securities | 0 | 0
Recurring items [Member] | Level 3 [Member] | US Treasury Securities |  |
AFS Securities |  |
AFS securities | 0 | 0
Nonrecurring items [Member] |  |
AFS Securities |  |
Impaired loans (net of the allowance for loan losses) | 391 | 17,143
Foreclosed Assets, Fair Value Disclosure | 509 | 439
Nonrecurring items [Member] | Level 1 [Member] |  |
AFS Securities |  |
Impaired loans (net of the allowance for loan losses) | 0 | 0
Foreclosed Assets, Fair Value Disclosure | 0 | 0
Nonrecurring items [Member] | Level 2 [Member] |  |
AFS Securities |  |
Impaired loans (net of the allowance for loan losses) | 0 | 0
Foreclosed Assets, Fair Value Disclosure | 0 | 0
Nonrecurring items [Member] | Level 3 [Member] |  |
AFS Securities |  |
Impaired loans (net of the allowance for loan losses) | 391 | 17,143
Foreclosed Assets, Fair Value Disclosure | $ 509 | $ 439

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