Loans - Loans (Detail) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022
Loans:
Loans - Gross	$ 2,448,155	$ 2,357,903
Less: Net deferred loan fees and costs	(1,503)	(1,516)
Loans after net deferred loan fees and costs	2,446,652	2,356,387	$ 1,962,220
Less: Allowance for loan losses	(24,634)	(20,313)
Loans - Net	2,422,018	2,336,074
Consumer Real Estate [Member]
Loans:
Loans - Gross	502,974	494,423
Loans after net deferred loan fees and costs	502,968	494,423	410,064
Less: Allowance for loan losses	(3,623)	(998)
Agricultural Real Estate [Member]
Loans:
Loans - Gross	227,897	220,819
Loans after net deferred loan fees and costs	227,599	220,514	195,901
Less: Allowance for loan losses	(209)	(349)
Agricultural [Member]
Loans:
Loans - Gross	131,467	128,733
Loans after net deferred loan fees and costs	131,677	128,926	140,847
Less: Allowance for loan losses	(66)	(751)
Commercial Real Estate [Member]
Loans:
Loans - Gross	1,225,315	1,152,603
Loans after net deferred loan fees and costs	1,223,163	1,150,511	909,408
Less: Allowance for loan losses	(16,088)	(11,924)
Commercial and Industrial [Member]
Loans:
Loans - Gross	241,598	242,360
Loans after net deferred loan fees and costs		242,301
Consumer [Member]
Loans:
Loans - Gross	89,588	89,147
Loans after net deferred loan fees and costs	90,388	89,894	$ 57,638
Less: Allowance for loan losses	(1,234)	(909)
Other Loan [Member]
Loans:
Loans - Gross	$ 29,316	29,818
Loans after net deferred loan fees and costs		$ 29,818

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

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