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Fair Value (Recorded amount of assets and liabilities measured at fair value) (Details) - USD ($) $ in Thousands | Mar. 31, 2022 | Dec. 31, 2021
--- | --- | ---
AFS Securities |  |
AFS securities | $ 544,919 | $ 490,601
Fair value, total | 560,558 | 509,624
US Treasury Securities |  |
AFS Securities |  |
AFS securities | 218,268 | 209,703
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 | $ 544,919 | $ 490,601
Percent of assets and liabilities measured at fair value | 97.21% | 96.27%
Level 3 [Member] |  |
AFS Securities |  |
Fair value, total | $ 15,639 | $ 19,023
Percent of assets and liabilities measured at fair value | 2.79% | 3.73%
Recurring items [Member] |  |
AFS Securities |  |
AFS securities | $ 544,919 | $ 490,601
Recurring items [Member] | States and political subdivisions [Member] |  |
AFS Securities |  |
AFS securities | 114,015 | 121,205
Recurring items [Member] | Auction rate money market preferred [Member] |  |
AFS Securities |  |
AFS securities | 2,867 | 3,242
Recurring items [Member] | Mortgage-backed securities [Member] |  |
AFS Securities |  |
AFS securities | 49,578 | 56,148
Recurring items [Member] | Collateralized mortgage obligations [Member] |  |
AFS Securities |  |
AFS securities | 152,441 | 92,301
Recurring items [Member] | Corporate Debt Securities |  |
AFS Securities |  |
AFS securities | 7,750 | 8,002
Recurring items [Member] | US Treasury Securities |  |
AFS Securities |  |
AFS securities | 218,268 | 209,703
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 | 544,919 | 490,601
Recurring items [Member] | Level 2 [Member] | States and political subdivisions [Member] |  |
AFS Securities |  |
AFS securities | 114,015 | 121,205
Recurring items [Member] | Level 2 [Member] | Auction rate money market preferred [Member] |  |
AFS Securities |  |
AFS securities | 2,867 | 3,242
Recurring items [Member] | Level 2 [Member] | Mortgage-backed securities [Member] |  |
AFS Securities |  |
AFS securities | 49,578 | 56,148
Recurring items [Member] | Level 2 [Member] | Collateralized mortgage obligations [Member] |  |
AFS Securities |  |
AFS securities | 152,441 | 92,301
Recurring items [Member] | Level 2 [Member] | Corporate Debt Securities |  |
AFS Securities |  |
AFS securities | 7,750 | 8,002
Recurring items [Member] | Level 2 [Member] | US Treasury Securities |  |
AFS Securities |  |
AFS securities | 218,268 | 209,703
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) | 15,639 | 18,812
Foreclosed Assets, Fair Value Disclosure | 0 | 211
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) | 15,639 | 18,812
Foreclosed Assets, Fair Value Disclosure | $ 0 | $ 211

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