Loans and Allowance for Credit Losses - Additional Information (Details)	12 Months Ended
	Dec. 31, 2023 USD ($) Alternative Loan_modified	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Jan. 01, 2020 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Increase (decrease) in accounts and notes receivable	$ 740,100,000
Accrued interest on loans	29,900,000	$ 23,000,000.0
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	$ 68,675,000	59,093,000	$ 54,655,000	$ 41,910,000
Recorded balance of nonaccrual loans	18,832,000	15,956,000
Interest lost on nonaccrual loans	$ 412,000	103,000	308,000
Troubled debt restructurings balance | Loan_modified	0
Real estate acquired through foreclosure	$ 1,163,000	4,261,000
Mortgage loans secured by real estate In foreclosure	$ 399,000	425,000
ASU 2016-13 | Financial Asset Acquired with Credit Deterioration | Revision of Prior Period, Adjustment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses					$ 833,000
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	$ 10,237,000	7,640,000
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	$ 4,940,000	4,943,000
Jefferson Bank
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans acquired amount	$ 730,200,000
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	one year
Agricultural | Real Estate Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses	$ 1,366,000	1,433,000	1,257,000	1,084,000
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	one year
Allowance for credit losses	$ 25,450,000	$ 20,808,000	$ 19,241,000	$ 13,485,000
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