v3.26.1
Loans and Allowance for Credit Losses - Schedule of Allowance for Credit Losses on Off-Balance Sheet Credit Exposures (Detail) - USD ($)
$ in Thousands
Mar. 31, 2026
Dec. 31, 2025
Mar. 31, 2025
Dec. 31, 2024
Accounts Notes And Loans Receivable [Line Items]        
Loans, allowance for credit losses $ 64,245 $ 52,756 $ 45,824 $ 43,267
SEC Schedule, 12-09, Allowance, Credit Loss [Member] | Off Balance Sheet Credit Loss Liability [Member]        
Accounts Notes And Loans Receivable [Line Items]        
Loans, allowance for credit losses 2,501 1,753    
Commercial Real Estate [Member]        
Accounts Notes And Loans Receivable [Line Items]        
Loans, allowance for credit losses 22,882 20,037 16,122 14,948
Commercial Real Estate [Member] | SEC Schedule, 12-09, Allowance, Credit Loss [Member] | Off Balance Sheet Credit Loss Liability [Member]        
Accounts Notes And Loans Receivable [Line Items]        
Loans, allowance for credit losses 301 272    
Commercial and Industrial [Member]        
Accounts Notes And Loans Receivable [Line Items]        
Loans, allowance for credit losses 23,850 17,830 13,548 14,005
Commercial and Industrial [Member] | SEC Schedule, 12-09, Allowance, Credit Loss [Member] | Off Balance Sheet Credit Loss Liability [Member]        
Accounts Notes And Loans Receivable [Line Items]        
Loans, allowance for credit losses 2,010 1,409    
Agricultural Real Estate [Member]        
Accounts Notes And Loans Receivable [Line Items]        
Loans, allowance for credit losses 7,665 4,669 5,158 3,504
Agricultural Real Estate [Member] | SEC Schedule, 12-09, Allowance, Credit Loss [Member] | Off Balance Sheet Credit Loss Liability [Member]        
Accounts Notes And Loans Receivable [Line Items]        
Loans, allowance for credit losses 16 4    
Residential Real Estate [Member]        
Accounts Notes And Loans Receivable [Line Items]        
Loans, allowance for credit losses 7,701 8,068 8,827 8,553
Residential Real Estate [Member] | SEC Schedule, 12-09, Allowance, Credit Loss [Member] | Off Balance Sheet Credit Loss Liability [Member]        
Accounts Notes And Loans Receivable [Line Items]        
Loans, allowance for credit losses 85 47    
Agricultural [Member]        
Accounts Notes And Loans Receivable [Line Items]        
Loans, allowance for credit losses 291 337 356 439
Agricultural [Member] | SEC Schedule, 12-09, Allowance, Credit Loss [Member] | Off Balance Sheet Credit Loss Liability [Member]        
Accounts Notes And Loans Receivable [Line Items]        
Loans, allowance for credit losses 5      
Consumer [Member]        
Accounts Notes And Loans Receivable [Line Items]        
Loans, allowance for credit losses 1,856 1,815 $ 1,813 $ 1,818
Consumer [Member] | SEC Schedule, 12-09, Allowance, Credit Loss [Member] | Off Balance Sheet Credit Loss Liability [Member]        
Accounts Notes And Loans Receivable [Line Items]        
Loans, allowance for credit losses $ 84 $ 21