v3.26.1
Loans Held-for-Investment and Allowance for Credit Losses - Summary of information on the allowance for credit losses (Detail) - USD ($)
 3 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Financing Receivable, Allowance for Credit Losses [Line Items]    
Beginning balance $ 105,536,000 $ 98,325,000
Provision for loan losses [1] 2,738,000 2,991,000
Charge-offs (1,174,000) (946,000)
Recoveries 818,000 710,000
Ending balance 107,918,000 101,080,000
Commercial [Member] | Commercial & Industrial [Member]    
Financing Receivable, Allowance for Credit Losses [Line Items]    
Beginning balance 17,696,000 15,436,000
Provision for loan losses [1] 2,663,000 154,000
Charge-offs (238,000) (91,000)
Recoveries 594,000 93,000
Ending balance 20,715,000 15,592,000
Commercial [Member] | Municipal [Member]    
Financing Receivable, Allowance for Credit Losses [Line Items]    
Beginning balance 135,000 200,000
Provision for loan losses [1] 117,000 160,000
Charge-offs 0 0
Recoveries 0 0
Ending balance 252,000 360,000
Agriculture [Member]    
Financing Receivable, Allowance for Credit Losses [Line Items]    
Beginning balance 325,000 1,653,000
Provision for loan losses [1] 54,000 (125,000)
Charge-offs (40,000) 0
Recoveries 0 36,000
Ending balance 339,000 1,564,000
Real Estate [Member] | Construction & Development [Member]    
Financing Receivable, Allowance for Credit Losses [Line Items]    
Beginning balance 17,000,000 19,861,000
Provision for loan losses [1] 636,000 (144,000)
Charge-offs (22,000) 0
Recoveries 0 0
Ending balance 17,614,000 19,717,000
Real Estate [Member] | Farm [Member]    
Financing Receivable, Allowance for Credit Losses [Line Items]    
Beginning balance 2,577,000 2,871,000
Provision for loan losses [1] (89,000) 47,000
Charge-offs 0 0
Recoveries 0 1,000
Ending balance 2,488,000 2,919,000
Real Estate [Member] | Non-Owner Occupied CRE [Member]    
Financing Receivable, Allowance for Credit Losses [Line Items]    
Beginning balance 14,561,000 14,664,000
Provision for loan losses [1] (706,000) 1,042,000
Charge-offs 0 0
Recoveries 14,000 3,000
Ending balance 13,869,000 15,709,000
Real Estate [Member] | Owner Occupied CRE [Member]    
Financing Receivable, Allowance for Credit Losses [Line Items]    
Beginning balance 25,368,000 21,413,000
Provision for loan losses [1] (885,000) (48,000)
Charge-offs (150,000) (175,000)
Recoveries 3,000 302,000
Ending balance 24,336,000 21,492,000
Real Estate [Member] | Residential [Member]    
Financing Receivable, Allowance for Credit Losses [Line Items]    
Beginning balance 25,614,000 20,488,000
Provision for loan losses [1] 449,000 1,498,000
Charge-offs (140,000) (250,000)
Recoveries 21,000 3,000
Ending balance 25,944,000 21,739,000
Consumer [Member] | Auto [Member]    
Financing Receivable, Allowance for Credit Losses [Line Items]    
Beginning balance 1,598,000 1,186,000
Provision for loan losses [1] 501,000 450,000
Charge-offs (358,000) (339,000)
Recoveries 115,000 198,000
Ending balance 1,856,000 1,495,000
Consumer [Member] | Non-Auto [Member]    
Financing Receivable, Allowance for Credit Losses [Line Items]    
Beginning balance 662,000 553,000
Provision for loan losses [1] (2,000) (43,000)
Charge-offs (226,000) (91,000)
Recoveries 71,000 74,000
Ending balance $ 505,000 $ 493,000
[1] For the three-months ended March 31, 2026 and 2025, the provision for credit losses of $2,291,000 and $3,528,000, respectively, on the consolidated statements of earnings includes a provision for credit losses on loans of $2,738,000 and $2,991,000, respectively, and a reversal of provision for off-balance sheet unfunded commitments of $447,000, and provision for off-balance sheet unfunded commitments of $537,000, respectively.