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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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
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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

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

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Fair value portion of investments in an entity not consolidated. Includes, but is not limited to, investments in an entity that is affiliated with the reporting entity by means of direct or indirect ownership, an entity in which the reporting entity shares control of the entity with another party or group, an entity which the company has significant influence, but does not have control and subsidiaries that are not required to be consolidated and are accounted for using the equity or cost method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19190-110258

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