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Loans - Classes of Loans (Details) - USD ($)	Sep. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Exclude accrued interest receivable from the amortized cost basis of loans	$ 7,190,000
Subtotal	1,717,729,000	$ 1,635,718,000
Less allowance for credit losses	(40,248,000)	(40,518,000)	$ (40,880,000)	$ (40,157,000)
Loans, net	1,677,481,000	1,595,200,000
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal	645,467,000	592,301,000
Commercial business
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal	118,641,000	118,605,000
Construction - commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal	62,994,000	49,136,000
Land acquisition and development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal	28,400,000	37,537,000
Builder lines
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal	30,787,000	34,538,000
Construction - consumer real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal	12,046,000	10,539,000
Residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal	290,325,000	266,267,000
Less allowance for credit losses		(2,622,000)	(2,670,000)	(2,660,000)
Equity lines
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal	48,027,000	43,300,000
Less allowance for credit losses		(497,000)	(535,000)	(593,000)
Other consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal	9,867,000	8,938,000
Amount included related to demand deposit overdrafts	207,000	284,000
Consumer finance
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal	471,175,000
Less allowance for credit losses	(24,389,000)	(25,969,000)	$ (26,262,000)	$ (24,791,000)
Consumer finance \| Automobiles
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal	403,154,000	411,112,000
Consumer finance \| Marine and recreational vehicles
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal	$ 68,021,000	$ 63,445,000