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Fair Value (Recorded amount of assets and liabilities measured at fair value) (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
AFS Securities
AFS securities	$ 516,897	$ 580,481
Fair value, total	517,797	598,063
US Treasury Securities
AFS Securities
AFS securities	209,182	208,701
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	$ 516,897	$ 580,481
Percent of assets and liabilities measured at fair value	99.83%	97.06%
Level 3 [Member]
AFS Securities
Fair value, total	$ 900	$ 17,582
Percent of assets and liabilities measured at fair value	0.17%	2.94%
Recurring items [Member]
AFS Securities
AFS securities	$ 516,897	$ 580,481
Recurring items [Member] | States and political subdivisions [Member]
AFS Securities
AFS securities	89,773	117,512
Recurring items [Member] | Auction rate money market preferred [Member]
AFS Securities
AFS securities	2,570	2,342
Recurring items [Member] | Mortgage-backed securities [Member]
AFS Securities
AFS securities	32,923	39,070
Recurring items [Member] | Collateralized mortgage obligations [Member]
AFS Securities
AFS securities	175,630	205,728
Recurring items [Member] | Corporate Debt Securities
AFS Securities
AFS securities	6,819	7,128
Recurring items [Member] | US Treasury Securities
AFS Securities
AFS securities	209,182	208,701
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	516,897	580,481
Recurring items [Member] | Level 2 [Member] | States and political subdivisions [Member]
AFS Securities
AFS securities	89,773	117,512
Recurring items [Member] | Level 2 [Member] | Auction rate money market preferred [Member]
AFS Securities
AFS securities	2,570	2,342
Recurring items [Member] | Level 2 [Member] | Mortgage-backed securities [Member]
AFS Securities
AFS securities	32,923	39,070
Recurring items [Member] | Level 2 [Member] | Collateralized mortgage obligations [Member]
AFS Securities
AFS securities	175,630	205,728
Recurring items [Member] | Level 2 [Member] | Corporate Debt Securities
AFS Securities
AFS securities	6,819	7,128
Recurring items [Member] | Level 2 [Member] | US Treasury Securities
AFS Securities
AFS securities	209,182	208,701
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)	391	17,143
Foreclosed Assets, Fair Value Disclosure	509	439
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)	391	17,143
Foreclosed Assets, Fair Value Disclosure	$ 509	$ 439

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
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-Publisher FASB
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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aa)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481830/320-10-45-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479130/326-30-45-1

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