Fair Value (Recorded amount of assets and liabilities measured at fair value) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
AFS Securities
AFS securities	$ 494,834	$ 548,730
Debt Securities, Available-for-sale	494,834	548,730
Available-for-sale Securities, Equity Securities	0	3,577
Fair value, total	515,202	568,554
Level 1 [Member]
AFS Securities
Fair value, total	$ 0	$ 3,577
Percent of assets and liabilities measured at fair value	0.00%	0.63%
Level 2 [Member]
AFS Securities
Fair value, total	$ 495,157	$ 549,021
Percent of assets and liabilities measured at fair value	96.11%	96.56%
Level 3 [Member]
AFS Securities
Fair value, total	$ 20,045	$ 15,956
Percent of assets and liabilities measured at fair value	3.89%	2.81%
Recurring items [Member]
AFS Securities
AFS securities	$ 494,834	$ 548,730
Available-for-sale Securities, Equity Securities	0	3,577
Derivative Assets (Liabilities), at Fair Value, Net	323	291
Recurring items [Member] \| Government sponsored enterprises [Member]
AFS Securities
AFS securities	170	216
Recurring items [Member] \| States and political subdivisions [Member]
AFS Securities
AFS securities	190,866	208,474
Recurring items [Member] \| Auction rate money market preferred [Member]
AFS Securities
AFS securities	2,554	3,049
Recurring items [Member] \| Mortgage-backed securities [Member]
AFS Securities
AFS securities	184,484	208,797
Recurring items [Member] \| Collateralized mortgage obligations [Member]
AFS Securities
AFS securities	116,760	128,194
Recurring items [Member] \| Level 1 [Member]
AFS Securities
AFS securities	0	0
Available-for-sale Securities, Equity Securities	0	3,577
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	494,834	548,730
Available-for-sale Securities, Equity Securities	0	0
Derivative Assets (Liabilities), at Fair Value, Net	323	291
Recurring items [Member] \| Level 2 [Member] \| Government sponsored enterprises [Member]
AFS Securities
Debt Securities, Available-for-sale	170	216
Recurring items [Member] \| Level 2 [Member] \| States and political subdivisions [Member]
AFS Securities
Debt Securities, Available-for-sale	190,866	208,474
Recurring items [Member] \| Level 2 [Member] \| Auction rate money market preferred [Member]
AFS Securities
Debt Securities, Available-for-sale	2,554	3,049
Recurring items [Member] \| Level 2 [Member] \| Mortgage-backed securities [Member]
AFS Securities
Debt Securities, Available-for-sale	184,484	208,797
Recurring items [Member] \| Level 2 [Member] \| Collateralized mortgage obligations [Member]
AFS Securities
Debt Securities, Available-for-sale	116,760	128,194
Recurring items [Member] \| Level 3 [Member]
AFS Securities
AFS securities	0	0
Available-for-sale Securities, Equity 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)	20,045	15,956
Nonrecurring items [Member] \| Level 1 [Member]
AFS Securities
Impaired loans (net of the allowance for loan losses)	0	0
Nonrecurring items [Member] \| Level 2 [Member]
AFS Securities
Impaired loans (net of the allowance for loan losses)	0	0
Nonrecurring items [Member] \| Level 3 [Member]
AFS Securities
Impaired loans (net of the allowance for loan losses)	$ 20,045	$ 15,956

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
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