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Fair Value (Recorded amount of assets and liabilities measured at fair value) (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
AFS Securities
AFS securities	$ 544,919	$ 490,601
Fair value, total	560,558	509,624
US Treasury Securities
AFS Securities
AFS securities	218,268	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	$ 544,919	$ 490,601
Percent of assets and liabilities measured at fair value	97.21%	96.27%
Level 3 [Member]
AFS Securities
Fair value, total	$ 15,639	$ 19,023
Percent of assets and liabilities measured at fair value	2.79%	3.73%
Recurring items [Member]
AFS Securities
AFS securities	$ 544,919	$ 490,601
Recurring items [Member] | States and political subdivisions [Member]
AFS Securities
AFS securities	114,015	121,205
Recurring items [Member] | Auction rate money market preferred [Member]
AFS Securities
AFS securities	2,867	3,242
Recurring items [Member] | Mortgage-backed securities [Member]
AFS Securities
AFS securities	49,578	56,148
Recurring items [Member] | Collateralized mortgage obligations [Member]
AFS Securities
AFS securities	152,441	92,301
Recurring items [Member] | Corporate Debt Securities
AFS Securities
AFS securities	7,750	8,002
Recurring items [Member] | US Treasury Securities
AFS Securities
AFS securities	218,268	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	544,919	490,601
Recurring items [Member] | Level 2 [Member] | States and political subdivisions [Member]
AFS Securities
AFS securities	114,015	121,205
Recurring items [Member] | Level 2 [Member] | Auction rate money market preferred [Member]
AFS Securities
AFS securities	2,867	3,242
Recurring items [Member] | Level 2 [Member] | Mortgage-backed securities [Member]
AFS Securities
AFS securities	49,578	56,148
Recurring items [Member] | Level 2 [Member] | Collateralized mortgage obligations [Member]
AFS Securities
AFS securities	152,441	92,301
Recurring items [Member] | Level 2 [Member] | Corporate Debt Securities
AFS Securities
AFS securities	7,750	8,002
Recurring items [Member] | Level 2 [Member] | US Treasury Securities
AFS Securities
AFS securities	218,268	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)	15,639	18,812
Foreclosed Assets, Fair Value Disclosure	0	211
Nonrecurring items [Member] | Level 1 [Member]
AFS Securities
Impaired loans (net of the allowance for loan losses)	0	0
Foreclosed Assets, Fair Value Disclosure	0	0
Nonrecurring items [Member] | Level 2 [Member]
AFS Securities
Impaired loans (net of the allowance for loan losses)	0	0
Foreclosed Assets, Fair Value Disclosure	0	0
Nonrecurring items [Member] | Level 3 [Member]
AFS Securities
Impaired loans (net of the allowance for loan losses)	15,639	18,812
Foreclosed Assets, Fair Value Disclosure	$ 0	$ 211

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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