Fair Value (Recorded amount of assets and liabilities measured at fair value) (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
AFS Securities
AFS securities	$ 448,454	$ 339,228
Fair value, total	472,625	361,130
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	$ 450,662	$ 341,590
Percent of assets and liabilities measured at fair value	95.35%	94.59%
Level 3 [Member]
AFS Securities
Fair value, total	$ 21,963	$ 19,540
Percent of assets and liabilities measured at fair value	4.65%	5.41%
Recurring items [Member]
AFS Securities
AFS securities	$ 448,454	$ 339,228
Derivative instruments	0	54
Recurring items [Member] \| States and political subdivisions [Member]
AFS Securities
AFS securities	130,960	143,656
Recurring items [Member] \| Auction rate money market preferred [Member]
AFS Securities
AFS securities	3,260	3,237
Recurring items [Member] \| Mortgage-backed securities [Member]
AFS Securities
AFS securities	68,155	88,652
Recurring items [Member] \| Collateralized mortgage obligations [Member]
AFS Securities
AFS securities	109,294	101,983
Recurring items [Member] \| Corporate Debt Securities
AFS Securities
AFS securities	4,192	1,700
Recurring items [Member] \| US Treasury Securities
AFS Securities
AFS securities	132,593	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	448,454	339,228
Derivative instruments	0	54
Recurring items [Member] \| Level 2 [Member] \| States and political subdivisions [Member]
AFS Securities
AFS securities	130,960	143,656
Recurring items [Member] \| Level 2 [Member] \| Auction rate money market preferred [Member]
AFS Securities
AFS securities	3,260	3,237
Recurring items [Member] \| Level 2 [Member] \| Mortgage-backed securities [Member]
AFS Securities
AFS securities	68,155	88,652
Recurring items [Member] \| Level 2 [Member] \| Collateralized mortgage obligations [Member]
AFS Securities
AFS securities	109,294	101,983
Recurring items [Member] \| Level 2 [Member] \| Corporate Debt Securities
AFS Securities
AFS securities	4,192	1,700
Recurring items [Member] \| Level 2 [Member] \| US Treasury Securities
AFS Securities
AFS securities	132,593	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)	21,963	19,540
Other Mortgage Servicing Rights, Fair Value Disclosure	2,208	2,308
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	2,208	2,308
Nonrecurring items [Member] \| Level 3 [Member]
AFS Securities
Impaired loans (net of the allowance for loan losses)	21,963	19,540
Other Mortgage Servicing Rights, Fair Value Disclosure	$ 0	$ 0

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Other Mortgage Servicing Rights, Fair Value Disclosure

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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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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 942
-SubTopic 210
-Section S99
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
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-Publisher FASB
-Name Accounting Standards Codification
-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

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-Publisher FASB
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-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=117331979&loc=d3e41228-113958

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