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Fair Value (Recorded amount of assets and liabilities measured at fair value) (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
AFS Securities
AFS securities	$ 557,590	$ 490,601
Fair value, total	572,554	509,413
US Treasury Securities
AFS Securities
AFS securities	214,474	209,703
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	$ 557,590	$ 490,601
Percent of assets and liabilities measured at fair value	97.39%	96.31%
Level 3 [Member]
AFS Securities
Fair value, total	$ 14,964	$ 18,812
Percent of assets and liabilities measured at fair value	2.61%	3.69%
Recurring items [Member]
AFS Securities
AFS securities	$ 557,590	$ 490,601
Recurring items [Member] | States and political subdivisions [Member]
AFS Securities
AFS securities	119,649	121,205
Recurring items [Member] | Auction rate money market preferred [Member]
AFS Securities
AFS securities	2,497	3,242
Recurring items [Member] | Mortgage-backed securities [Member]
AFS Securities
AFS securities	45,796	56,148
Recurring items [Member] | Collateralized mortgage obligations [Member]
AFS Securities
AFS securities	167,572	92,301
Recurring items [Member] | Corporate Debt Securities
AFS Securities
AFS securities	7,602	8,002
Recurring items [Member] | US Treasury Securities
AFS Securities
AFS securities	214,474	209,703
Recurring items [Member] | Level 1 [Member]
AFS Securities
AFS securities	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	557,590	490,601
Recurring items [Member] | Level 2 [Member] | States and political subdivisions [Member]
AFS Securities
AFS securities	119,649	121,205
Recurring items [Member] | Level 2 [Member] | Auction rate money market preferred [Member]
AFS Securities
AFS securities	2,497	3,242
Recurring items [Member] | Level 2 [Member] | Mortgage-backed securities [Member]
AFS Securities
AFS securities	45,796	56,148
Recurring items [Member] | Level 2 [Member] | Collateralized mortgage obligations [Member]
AFS Securities
AFS securities	167,572	92,301
Recurring items [Member] | Level 2 [Member] | Corporate Debt Securities
AFS Securities
AFS securities	7,602	8,002
Recurring items [Member] | Level 2 [Member] | US Treasury Securities
AFS Securities
AFS securities	214,474	209,703
Recurring items [Member] | Level 3 [Member]
AFS Securities
AFS securities	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)	14,964	18,812
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)	$ 14,964	$ 18,812

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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