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Loans - Classes of Loans (Details) - USD ($)	Sep. 30, 2024	Dec. 31, 2023	Sep. 30, 2023	Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Exclude accrued interest receivable from the amortized cost basis of loans	$ 7,930,000	$ 7,650,000
Subtotal	1,909,409,000	1,742,139,000
Less allowance for credit losses	(40,771,000)	(39,651,000)	$ (40,248,000)	$ (40,518,000)
Loans, net	1,868,638,000	1,702,488,000
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal	701,647,000	668,122,000
Commercial business
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal	115,410,000	115,348,000
Construction - commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal	155,072,000	69,768,000
Land acquisition and development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal	33,774,000	29,064,000
Builder lines
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal	29,664,000	24,668,000
Construction - consumer real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal	16,874,000	11,223,000
Residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal	310,595,000	293,256,000
Equity lines
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal	59,406,000	51,592,000
Other consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal	9,667,000	10,588,000
Amount included related to demand deposit overdrafts	210,000	228,000
Consumer finance
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal	477,300,000	468,510,000
Less allowance for credit losses	(23,238,000)	(23,578,000)	$ (24,389,000)	$ (25,969,000)
Consumer finance \| Automobiles
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal	406,385,000	401,276,000
Consumer finance \| Marine and recreational vehicles
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal	$ 70,915,000	$ 67,234,000