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Fair Value (Recorded amount of assets and liabilities measured at fair value) (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
AFS Securities |  |
AFS securities | $ 339,228 | $ 429,839
Debt Securities, Available-for-sale | 339,228 | 429,839
Fair value, total | 361,657 | 456,007
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 | $ 341,590 | $ 432,170
Percent of assets and liabilities measured at fair value | 94.45% | 94.77%
Level 3 [Member] |  |
AFS Securities |  |
Fair value, total | $ 20,067 | $ 23,837
Percent of assets and liabilities measured at fair value | 5.55% | 5.23%
Recurring items [Member] |  |
AFS Securities |  |
AFS securities | $ 339,228 | $ 429,839
Derivative Assets (Liabilities), at Fair Value, Net | 54 | 67
Recurring items [Member] | States and political subdivisions [Member] |  |
AFS Securities |  |
AFS securities | 143,656 | 169,752
Recurring items [Member] | Auction rate money market preferred [Member] |  |
AFS Securities |  |
AFS securities | 3,237 | 3,119
Recurring items [Member] | Mortgage-backed securities [Member] |  |
AFS Securities |  |
AFS securities | 88,652 | 140,204
Recurring items [Member] | Collateralized mortgage obligations [Member] |  |
AFS Securities |  |
AFS securities | 101,983 | 116,764
Recurring items [Member] | Corporate Debt Securities |  |
AFS Securities |  |
AFS securities | 1,700 | 0
Recurring items [Member] | Level 1 [Member] |  |
AFS Securities |  |
AFS securities | 0 | 0
Derivative Assets (Liabilities), at Fair Value, Net | 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 |  |
AFS securities | 339,228 | 429,839
Derivative Assets (Liabilities), at Fair Value, Net | (54) | 67
Recurring items [Member] | Level 2 [Member] | States and political subdivisions [Member] |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 143,656 | 169,752
Recurring items [Member] | Level 2 [Member] | Auction rate money market preferred [Member] |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 3,237 | 3,119
Recurring items [Member] | Level 2 [Member] | Mortgage-backed securities [Member] |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 88,652 | 140,204
Recurring items [Member] | Level 2 [Member] | Collateralized mortgage obligations [Member] |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 101,983 | 116,764
Recurring items [Member] | Level 2 [Member] | Corporate Debt Securities |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 1,700 | 0
Recurring items [Member] | Level 3 [Member] |  |
AFS Securities |  |
AFS securities | 0 | 0
Derivative Assets (Liabilities), at Fair Value, Net | 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) | 19,540 | 19,135
OMSR | 2,308 | 2,264
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures | 0 | 4,246
Foreclosed assets | 527 | 456
Nonrecurring items [Member] | Level 1 [Member] |  |
AFS Securities |  |
Impaired loans (net of the allowance for loan losses) | 0 | 0
OMSR | 0 | 0
Investment in CSS | 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
OMSR | 2,308 | 2,264
Investment in CSS | 0 | 0
Foreclosed assets | 0 | 0
Nonrecurring items [Member] | Level 3 [Member] |  |
AFS Securities |  |
Impaired loans (net of the allowance for loan losses) | 19,540 | 19,135
OMSR | 0 | 0
Investment in CSS | 0 | 4,246
Foreclosed assets | $ 527 | $ 456

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