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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

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Loans and Allowance for Credit Losses - Additional Information (Details)	12 Months Ended
	Dec. 31, 2024 USD ($) Alternative Loan_modified	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Increase (decrease) in accounts and notes receivable	$ 88,800,000
Accrued interest on loans	33,700,000	$ 29,900,000
Minimum value of loans individually measured for impairment	$ 250,000,000
Number of alternatives for measuring impaired loans receivable \| Alternative	3
Allowance for credit losses	$ 70,182,000	68,675,000	$ 59,093,000	$ 54,655,000
Recorded balance of nonaccrual loans	28,775,000	18,832,000
Interest lost on nonaccrual loans	$ 1,400,000	412,000	103,000
Troubled debt restructurings balance \| Loan_modified	0
Real estate acquired through foreclosure	$ 2,179,000	1,163,000
Mortgage loans secured by real estate In foreclosure	$ 2,800,000	399,000
Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Debt coverage ratio	1.20x
Amortization period of loans	twenty years
Recorded balance of nonaccrual loans	$ 7,716,000	10,237,000
Commercial Real Estate \| Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maximum loan-to-value ratio (in hundredths)	65.00%
Commercial Real Estate \| Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maximum loan-to-value ratio (in hundredths)	80.00%
1-4 Family Residential Properties
Accounts, Notes, Loans and Financing Receivable [Line Items]
Period when loans charged-down	180 days
Recorded balance of nonaccrual loans	$ 4,937,000	4,940,000
Unsecured Open-end Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Period when loans charged-down	180 days
Other Secured Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Period when loans charged-down	120 days
Agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maximum loan-to-value ratio (in hundredths)	65.00%
Amortization period of loans	twenty-five years
Loans receivable, time period	1 year
Agricultural \| Real Estate Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses	$ 1,361,000	1,366,000	1,433,000	1,257,000
Commercial and Industrial Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maximum loan-to-value ratio (in hundredths)	80.00%
Amortization period of loans	seven years
Loans receivable, time period	1 year
Percentage of increase (decrease) in qualitative factors	(10.00%)
Allowance for credit losses	$ 25,602,000	25,450,000	20,808,000	19,241,000
Residential Properties \| Real Estate Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maximum loan-to-value ratio (in hundredths)	80.00%
Amortization period of loans	twenty-five years
Balloon period	five years
Construction and Land Development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of amount on net basis	10.00%
Construction and Land Development \| Real Estate Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses	$ 3,275,000	2,918,000	2,250,000	1,743,000
Residential Real Estate Owner Occupied Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of increase (decrease) in qualitative factors	15.00%
HELOC Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of increase (decrease) in qualitative factors	15.00%
Commercial Real Estate Owner Occupied Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of increase (decrease) in qualitative factors	(10.00%)
Commercial Real Estate Non Owner Occupied Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of increase (decrease) in qualitative factors	5.00%
Agricultural Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of increase (decrease) in qualitative factors	25.00%
Allowance for credit losses	$ 1,957,000	705,000	585,000	983,000
Consumer Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of increase (decrease) in qualitative factors	15.00%
Allowance for credit losses	$ 1,739,000	$ 2,258,000	$ 2,118,000	$ 2,855,000