Loans and Allowance for Credit Losses - Schedule of Loans Evaluated for Impairment (Detail) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Financing Receivable Impaired [Line Items]
Individually evaluated for credit losses	$ 4,887	$ 4,765
Collectively evaluated for credit losses	38,380	38,755
Total Allowance for Loan Losses	43,267	43,520	$ 45,847	$ 48,365
Individually evaluated for credit losses	29,893	27,963
Collectively evaluated for credit losses	3,470,923	3,304,938
Total Loans	3,500,816	3,332,901
Commercial Real Estate [Member]
Financing Receivable Impaired [Line Items]
Individually evaluated for credit losses	1,053	582
Collectively evaluated for credit losses	13,895	12,894
Total Allowance for Loan Losses	14,948	13,476	16,731	22,478
Individually evaluated for credit losses	7,854	6,031
Collectively evaluated for credit losses	1,822,660	1,753,824
Total Loans	1,830,514	1,759,855
Commercial and Industrial [Member]
Financing Receivable Impaired [Line Items]
Individually evaluated for credit losses	1,618	1,644
Collectively evaluated for credit losses	12,387	16,310
Total Allowance for Loan Losses	14,005	17,954	14,951	12,248
Individually evaluated for credit losses	8,593	5,498
Collectively evaluated for credit losses	650,272	592,829
Total Loans	658,865	598,327
Residential Real Estate [Member]
Financing Receivable Impaired [Line Items]
Individually evaluated for credit losses	1,167	1,113
Collectively evaluated for credit losses	7,386	6,671
Total Allowance for Loan Losses	8,553	7,784	8,608	5,560
Individually evaluated for credit losses	4,996	7,495
Collectively evaluated for credit losses	561,770	548,833
Total Loans	566,766	556,328
Agricultural Real Estate [Member]
Financing Receivable Impaired [Line Items]
Individually evaluated for credit losses	701	674
Collectively evaluated for credit losses	2,803	1,044
Total Allowance for Loan Losses	3,504	1,718	819	2,235
Individually evaluated for credit losses	5,839	4,672
Collectively evaluated for credit losses	261,409	191,442
Total Loans	267,248	196,114
Agricultural [Member]
Financing Receivable Impaired [Line Items]
Individually evaluated for credit losses	147	598
Collectively evaluated for credit losses	292	397
Total Allowance for Loan Losses	439	995	2,457	3,756
Individually evaluated for credit losses	1,740	3,598
Collectively evaluated for credit losses	85,599	114,989
Total Loans	87,339	118,587
Consumer [Member]
Financing Receivable Impaired [Line Items]
Individually evaluated for credit losses	201	154
Collectively evaluated for credit losses	1,617	1,439
Total Allowance for Loan Losses	1,818	1,593	$ 2,281	$ 2,088
Individually evaluated for credit losses	871	669
Collectively evaluated for credit losses	89,213	103,021
Total Loans	$ 90,084	$ 103,690