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

Impaired Financing Receivable, Fair Value Disclosure

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- Definition

Other Mortgage Servicing Rights, Fair Value Disclosure

+ References

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- Definition

Percent of assets and liabilities measured at fair value.

+ References

No definition available.

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- Definition

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
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
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- Definition

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 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109979856&loc=d3e26610-111562

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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- Definition

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
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

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