Fair Value (Recorded amount of assets and liabilities measured at fair value) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
AFS Securities
AFS securities	$ 367,324	$ 339,228
Fair value, total	395,516	361,657
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	$ 369,628	$ 341,590
Percent of assets and liabilities measured at fair value	93.45%	94.45%
Level 3 [Member]
AFS Securities
Fair value, total	$ 25,888	$ 20,067
Percent of assets and liabilities measured at fair value	6.55%	5.55%
Recurring items [Member]
AFS Securities
AFS securities	$ 367,324	$ 339,228
Derivative instruments	28	54
Recurring items [Member] \| States and political subdivisions [Member]
AFS Securities
AFS securities	140,329	143,656
Recurring items [Member] \| Auction rate money market preferred [Member]
AFS Securities
AFS securities	3,224	3,237
Recurring items [Member] \| Mortgage-backed securities [Member]
AFS Securities
AFS securities	75,835	88,652
Recurring items [Member] \| Collateralized mortgage obligations [Member]
AFS Securities
AFS securities	116,865	101,983
Recurring items [Member] \| Corporate Debt Securities
AFS Securities
AFS securities	1,700	1,700
Recurring items [Member] \| US Treasury Securities
AFS Securities
AFS securities	29,371	0
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 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	367,324	339,228
Derivative instruments	28	54
Recurring items [Member] \| Level 2 [Member] \| States and political subdivisions [Member]
AFS Securities
AFS securities	140,329	143,656
Recurring items [Member] \| Level 2 [Member] \| Auction rate money market preferred [Member]
AFS Securities
AFS securities	3,224	3,237
Recurring items [Member] \| Level 2 [Member] \| Mortgage-backed securities [Member]
AFS Securities
AFS securities	75,835	88,652
Recurring items [Member] \| Level 2 [Member] \| Collateralized mortgage obligations [Member]
AFS Securities
AFS securities	116,865	101,983
Recurring items [Member] \| Level 2 [Member] \| Corporate Debt Securities
AFS Securities
AFS securities	1,700	1,700
Recurring items [Member] \| Level 2 [Member] \| US Treasury Securities
AFS Securities
AFS securities	29,371	0
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
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)	25,504	19,540
Other Mortgage Servicing Rights, Fair Value Disclosure	2,276	2,308
Foreclosed Assets, Fair Value Disclosure	384	527
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
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
Other Mortgage Servicing Rights, Fair Value Disclosure	2,276	2,308
Foreclosed Assets, Fair Value Disclosure	0	0
Nonrecurring items [Member] \| Level 3 [Member]
AFS Securities
Impaired loans (net of the allowance for loan losses)	25,504	19,540
Other Mortgage Servicing Rights, Fair Value Disclosure	0	0
Foreclosed Assets, Fair Value Disclosure	$ 384	$ 527

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Percent of assets and liabilities measured at fair value.

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
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-Section 50
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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
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-URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454

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-Publisher FASB
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-Topic 320
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Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 10
-Section 45
-Paragraph 5
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