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Fair Value (Recorded amount of assets and liabilities measured at fair value) (Details) - USD ($) $ in Thousands | Mar. 31, 2020 | Dec. 31, 2019
--- | --- | ---
AFS Securities |  |
AFS securities | $ 407,189 | $ 429,839
Fair value, total | 428,039 | 451,305
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 | $ 409,261 | $ 432,170
Percent of assets and liabilities measured at fair value | 95.61% | 95.76%
Level 3 [Member] |  |
AFS Securities |  |
Fair value, total | $ 18,778 | $ 19,135
Percent of assets and liabilities measured at fair value | 4.39% | 4.24%
Recurring items [Member] |  |
AFS Securities |  |
AFS securities | $ 407,189 | $ 429,839
Derivative instruments | 69 | (67)
Recurring items [Member] | States and political subdivisions [Member] |  |
AFS Securities |  |
AFS securities | 163,116 | 169,752
Recurring items [Member] | Auction rate money market preferred [Member] |  |
AFS Securities |  |
AFS securities | 2,726 | 3,119
Recurring items [Member] | Mortgage-backed securities [Member] |  |
AFS Securities |  |
AFS securities | 126,554 | 140,204
Recurring items [Member] | Collateralized mortgage obligations [Member] |  |
AFS Securities |  |
AFS securities | 114,793 | 116,764
Recurring items [Member] | Level 1 [Member] |  |
AFS Securities |  |
AFS securities | 0 | 0
Derivative instruments | 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 2 [Member] |  |
AFS Securities |  |
AFS securities | 407,189 | 429,839
Derivative instruments | 69 | (67)
Recurring items [Member] | Level 2 [Member] | States and political subdivisions [Member] |  |
AFS Securities |  |
AFS securities | 163,116 | 169,752
Recurring items [Member] | Level 2 [Member] | Auction rate money market preferred [Member] |  |
AFS Securities |  |
AFS securities | 2,726 | 3,119
Recurring items [Member] | Level 2 [Member] | Mortgage-backed securities [Member] |  |
AFS Securities |  |
AFS securities | 126,554 | 140,204
Recurring items [Member] | Level 2 [Member] | Collateralized mortgage obligations [Member] |  |
AFS Securities |  |
AFS securities | 114,793 | 116,764
Recurring items [Member] | Level 3 [Member] |  |
AFS Securities |  |
AFS securities | 0 | 0
Derivative instruments | 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
Nonrecurring items [Member] |  |
AFS Securities |  |
Impaired loans (net of the allowance for loan losses) | 18,778 | 19,135
Other Mortgage Servicing Rights, Fair Value Disclosure | 2,003 | 2,264
Nonrecurring items [Member] | Level 1 [Member] |  |
AFS Securities |  |
Impaired loans (net of the allowance for loan losses) | 0 | 0
Other Mortgage Servicing Rights, Fair Value Disclosure | 0 | 0
Nonrecurring items [Member] | Level 2 [Member] |  |
AFS Securities |  |
Impaired loans (net of the allowance for loan losses) | 0 | 0
Other Mortgage Servicing Rights, Fair Value Disclosure | 2,003 | 2,264
Nonrecurring items [Member] | Level 3 [Member] |  |
AFS Securities |  |
Impaired loans (net of the allowance for loan losses) | 18,778 | 19,135
Other Mortgage Servicing Rights, Fair Value Disclosure | $ 0 | $ 0

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