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Fair Value (Recorded amount of assets and liabilities measured at fair value) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
AFS Securities
AFS securities	$ 363,054	$ 429,839
Fair value, total	384,650	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	$ 365,317	$ 432,170
Percent of assets and liabilities measured at fair value	94.97%	95.76%
Level 3 [Member]
AFS Securities
Fair value, total	$ 19,333	$ 19,135
Percent of assets and liabilities measured at fair value	5.03%	4.24%
Recurring items [Member]
AFS Securities
AFS securities	$ 363,054	$ 429,839
Derivative instruments	78	(67)
Recurring items [Member] | States and political subdivisions [Member]
AFS Securities
AFS securities	148,401	169,752
Recurring items [Member] | Auction rate money market preferred [Member]
AFS Securities
AFS securities	3,194	3,119
Recurring items [Member] | Mortgage-backed securities [Member]
AFS Securities
AFS securities	104,165	140,204
Recurring items [Member] | Collateralized mortgage obligations [Member]
AFS Securities
AFS securities	107,294	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	363,054	429,839
Derivative instruments	78	(67)
Recurring items [Member] | Level 2 [Member] | States and political subdivisions [Member]
AFS Securities
AFS securities	148,401	169,752
Recurring items [Member] | Level 2 [Member] | Auction rate money market preferred [Member]
AFS Securities
AFS securities	3,194	3,119
Recurring items [Member] | Level 2 [Member] | Mortgage-backed securities [Member]
AFS Securities
AFS securities	104,165	140,204
Recurring items [Member] | Level 2 [Member] | Collateralized mortgage obligations [Member]
AFS Securities
AFS securities	107,294	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)	19,333	19,135
Other Mortgage Servicing Rights, Fair Value Disclosure	2,185	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	2,185	2,264
Nonrecurring items [Member] | Level 3 [Member]
AFS Securities
Impaired loans (net of the allowance for loan losses)	19,333	19,135
Other Mortgage Servicing Rights, Fair Value Disclosure	$ 0	$ 0

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+ References

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-Publisher FASB
-Name Accounting Standards Codification
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