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Fair Value (Recorded amount of assets and liabilities measured at fair value) (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
AFS Securities
AFS securities	$ 506,806	$ 528,148
Fair value, total	509,927	532,059
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	$ 506,806	$ 530,570
Percent of assets and liabilities measured at fair value	99.39%	99.72%
Fair Value, Inputs, Level 3 [Member]
AFS Securities
Fair value, total	$ 3,121	$ 1,489
Percent of assets and liabilities measured at fair value	0.61%	0.28%
Recurring items [Member]
AFS Securities
AFS securities	$ 506,806	$ 528,148
Recurring items [Member] | US Treasury Securities
AFS Securities
AFS securities	220,829	214,801
Recurring items [Member] | States and political subdivisions [Member]
AFS Securities
AFS securities	82,899	92,876
Recurring items [Member] | Auction rate money market preferred [Member]
AFS Securities
AFS securities	3,117	2,931
Recurring items [Member] | Mortgage-backed securities [Member]
AFS Securities
AFS securities	28,955	32,815
Recurring items [Member] | Collateralized mortgage obligations [Member]
AFS Securities
AFS securities	163,764	177,775
Recurring items [Member] | Corporate Debt Securities
AFS Securities
AFS securities	7,242	6,950
Recurring items [Member] | Level 1 [Member]
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 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 2 [Member]
AFS Securities
AFS securities	506,806	528,148
Recurring items [Member] | Level 2 [Member] | US Treasury Securities
AFS Securities
AFS securities	220,829	214,801
Recurring items [Member] | Level 2 [Member] | States and political subdivisions [Member]
AFS Securities
AFS securities	82,899	92,876
Recurring items [Member] | Level 2 [Member] | Auction rate money market preferred [Member]
AFS Securities
AFS securities	3,117	2,931
Recurring items [Member] | Level 2 [Member] | Mortgage-backed securities [Member]
AFS Securities
AFS securities	28,955	32,815
Recurring items [Member] | Level 2 [Member] | Collateralized mortgage obligations [Member]
AFS Securities
AFS securities	163,764	177,775
Recurring items [Member] | Level 2 [Member] | Corporate Debt Securities
AFS Securities
AFS securities	7,242	6,950
Recurring items [Member] | Fair Value, Inputs, Level 3 [Member]
AFS Securities
AFS securities	0	0
Recurring items [Member] | Fair Value, Inputs, Level 3 [Member] | US Treasury Securities
AFS Securities
AFS securities	0	0
Recurring items [Member] | Fair Value, Inputs, Level 3 [Member] | States and political subdivisions [Member]
AFS Securities
AFS securities	0	0
Recurring items [Member] | Fair Value, Inputs, Level 3 [Member] | Auction rate money market preferred [Member]
AFS Securities
AFS securities	0	0
Recurring items [Member] | Fair Value, Inputs, Level 3 [Member] | Mortgage-backed securities [Member]
AFS Securities
AFS securities	0	0
Recurring items [Member] | Fair Value, Inputs, Level 3 [Member] | Collateralized mortgage obligations [Member]
AFS Securities
AFS securities	0	0
Recurring items [Member] | Fair Value, Inputs, Level 3 [Member] | Corporate Debt Securities
AFS Securities
AFS securities	0	0
Nonrecurring items [Member]
AFS Securities
Impaired loans (net of the allowance for loan losses)	357	1,083
Other Mortgage Servicing Rights, Fair Value Disclosure	2,218	2,422
Foreclosed Assets, Fair Value Disclosure	546	406
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
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
Other Mortgage Servicing Rights, Fair Value Disclosure	0	2,422
Foreclosed Assets, Fair Value Disclosure	0	0
Nonrecurring items [Member] | Fair Value, Inputs, Level 3 [Member]
AFS Securities
Impaired loans (net of the allowance for loan losses)	357	1,083
Other Mortgage Servicing Rights, Fair Value Disclosure	2,218	0
Foreclosed Assets, Fair Value Disclosure	$ 546	$ 406

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