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Loans and Allowance for Credit Losses - Additional Information (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2026 USD ($) Loan_modified	Jun. 30, 2025 USD ($) Loan_modified	Jun. 30, 2026 USD ($) Loan_modified Alternative	Jun. 30, 2025 USD ($) Loan_modified	Mar. 31, 2026 USD ($)	Dec. 31, 2025 USD ($)	Mar. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accrued interest on loans	$ 37,300,000		$ 37,300,000			$ 35,100,000
Gross loans	6,927,618,000		6,927,618,000			6,006,171,000
Increase in accounts and notes receivable			909,300,000
Allowance for credit losses	86,989,000	$ 71,160,000	$ 86,989,000	$ 71,160,000	$ 86,814,000	74,875,000	$ 70,051,000	$ 70,182,000
Number of alternatives for measuring impaired loans receivable \| Alternative			3
Recorded balance of nonaccrual loans	$ 40,429,000		$ 40,429,000			31,053,000
Interest lost on nonaccrual loans			$ 1,800,000	$ 662,000
Troubled debt restructurings balance \| Loan_modified	4	0	5	4
Real estate acquired through foreclosure	$ 5,803,000		$ 5,803,000			2,857,000
Mortgage loans secured by real estate In foreclosure	3,200,000		3,200,000			1,300,000
Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses	250,000		250,000
Minimum \| Substandard
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses	5,000,000		$ 5,000,000
Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Thresholds percentage of total capital			300.00%
Recorded balance of nonaccrual loans	$ 11,329,000		$ 11,329,000			10,381,000
Commercial Real Estate \| Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maximum loan-to-value ratio (in hundredths)			65.00%
Debt coverage ratio			1.20x
Amortization period of loans			twenty years
Commercial Real Estate \| Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maximum loan-to-value ratio (in hundredths)			85.00%
Debt coverage ratio			1.35x
Amortization period of loans			thirty years
1-4 Family Residential Properties
Accounts, Notes, Loans and Financing Receivable [Line Items]
Period when loans charged-down	180 days		180 days
Recorded balance of nonaccrual loans	$ 9,405,000		$ 9,405,000			5,763,000
Unsecured Open-end Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Period when loans charged-down	180 days		180 days
Other Secured Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Period when loans charged-down	120 days		120 days
Two Rivers Financial Group, Inc
Accounts, Notes, Loans and Financing Receivable [Line Items]
Increase in accounts and notes receivable			$ 860,500,000
Agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maximum loan-to-value ratio (in hundredths)			80.00%
Loans receivable, time period			1 year
Agricultural \| Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortization period of loans			twenty-five
Agricultural \| Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortization period of loans			thirty years
Agricultural \| Real Estate Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses	$ 1,385,000	$ 1,322,000	$ 1,385,000	$ 1,322,000	1,415,000	1,283,000	1,292,000	1,361,000
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
Allowance for credit losses	29,809,000	25,618,000	$ 29,809,000	25,618,000	28,553,000	26,285,000	26,028,000	25,602,000
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
Construction and Land Development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Thresholds percentage of total capital			100.00%
Construction and Land Development \| Real Estate Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses	5,129,000	$ 4,066,000	$ 5,129,000	$ 4,066,000	$ 4,940,000	$ 5,129,000	$ 3,731,000	$ 3,275,000
Construction and Land Development \| Real Estate Loan \| Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	$ 2,000,000		$ 2,000,000
Maximum loan-to-value ratio (in hundredths)			65.00%
Amortization period of loans			twenty
Construction and Land Development \| Real Estate Loan \| Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maximum loan-to-value ratio (in hundredths)			80.00%
Amortization period of loans			thirty years