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Fair Value (Recorded amount of assets and liabilities measured at fair value) (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
AFS Securities |  |
AFS securities | $ 429,839 | $ 494,834
Debt Securities, Available-for-sale | 429,839 | 494,834
Fair value, total | 456,007 | 525,556
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 | $ 429,906 | $ 495,157
Percent of assets and liabilities measured at fair value | 94.28% | 94.22%
Level 3 [Member] |  |
AFS Securities |  |
Fair value, total | $ 26,101 | $ 30,399
Percent of assets and liabilities measured at fair value | 5.72% | 5.78%
Recurring items [Member] |  |
AFS Securities |  |
AFS securities | $ 429,839 | $ 494,834
Derivative Assets (Liabilities), at Fair Value, Net | 67 | 323
Recurring items [Member] | Government sponsored enterprises [Member] |  |
AFS Securities |  |
AFS securities | 0 | 170
Recurring items [Member] | States and political subdivisions [Member] |  |
AFS Securities |  |
AFS securities | 169,752 | 190,866
Recurring items [Member] | Auction rate money market preferred [Member] |  |
AFS Securities |  |
AFS securities | 3,119 | 2,554
Recurring items [Member] | Mortgage-backed securities [Member] |  |
AFS Securities |  |
AFS securities | 140,204 | 184,484
Recurring items [Member] | Collateralized mortgage obligations [Member] |  |
AFS Securities |  |
AFS securities | 116,764 | 116,760
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] | Government sponsored enterprises [Member] |  |
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 2 [Member] |  |
AFS Securities |  |
AFS securities | 429,839 | 494,834
Derivative Assets (Liabilities), at Fair Value, Net | 67 | 323
Recurring items [Member] | Level 2 [Member] | Government sponsored enterprises [Member] |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 0 | 170
Recurring items [Member] | Level 2 [Member] | States and political subdivisions [Member] |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 169,752 | 190,866
Recurring items [Member] | Level 2 [Member] | Auction rate money market preferred [Member] |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 3,119 | 2,554
Recurring items [Member] | Level 2 [Member] | Mortgage-backed securities [Member] |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 140,204 | 184,484
Recurring items [Member] | Level 2 [Member] | Collateralized mortgage obligations [Member] |  |
AFS Securities |  |
Debt Securities, Available-for-sale | 116,764 | 116,760
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] | Government sponsored enterprises [Member] |  |
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
Nonrecurring items [Member] |  |
AFS Securities |  |
Impaired loans (net of the allowance for loan losses) | 19,135 | 20,045
OMSR | 2,264 | 2,434
Investment in CSS | 4,246 | 7,565
Foreclosed assets | 456 | 355
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 | 0 | 0
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) | 19,135 | 20,045
OMSR | 2,264 | 2,434
Investment in CSS | 4,246 | 7,565
Foreclosed assets | $ 456 | $ 355

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