v3.26.1
Loans Held-for-Investment and Allowance for Credit Losses - Summary of information on the allowance for credit losses (Detail) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Financing Receivable, Allowance for Credit Losses [Line Items]        
Beginning balance $ 107,918 $ 101,080 $ 105,536 $ 98,325
Provision for loan losses 3,915 [1] 2,432 [1] 6,653 [2] 5,423 [2]
Charge-offs (961) (1,189) (2,135) (2,135)
Recoveries 1,561 469 2,379 1,179
Ending balance 112,433 102,792 112,433 102,792
Commercial [Member] | Commercial & Industrial [Member]        
Financing Receivable, Allowance for Credit Losses [Line Items]        
Beginning balance 20,715 15,592 17,696 15,436
Provision for loan losses (994) [1] 2,502 [1] 1,669 [2] 2,656 [2]
Charge-offs (308) (320) (546) (411)
Recoveries 266 100 860 193
Ending balance 19,679 17,874 19,679 17,874
Commercial [Member] | Municipal [Member]        
Financing Receivable, Allowance for Credit Losses [Line Items]        
Beginning balance 252 360 135 200
Provision for loan losses 30 [1] 1 [1] 147 [2] 161 [2]
Charge-offs 0 0 0 0
Recoveries 0 0 0 0
Ending balance 282 361 282 361
Agriculture [Member]        
Financing Receivable, Allowance for Credit Losses [Line Items]        
Beginning balance 339 1,564 325 1,653
Provision for loan losses (200) [1] (665) [1] (146) [2] (790) [2]
Charge-offs (6) 0 (46) 0
Recoveries 41 38 41 74
Ending balance 174 937 174 937
Real Estate [Member] | Construction & Development [Member]        
Financing Receivable, Allowance for Credit Losses [Line Items]        
Beginning balance 17,614 19,717 17,000 19,861
Provision for loan losses 230 [1] 2,368 [1] 866 [2] 2,224 [2]
Charge-offs (29) (40) (51) (40)
Recoveries 0 2 0 2
Ending balance 17,815 22,047 17,815 22,047
Real Estate [Member] | Farm [Member]        
Financing Receivable, Allowance for Credit Losses [Line Items]        
Beginning balance 2,488 2,919 2,577 2,871
Provision for loan losses (118) [1] (135) [1] (207) [2] (88) [2]
Charge-offs 0 0 0 0
Recoveries 0 0 0 1
Ending balance 2,370 2,784 2,370 2,784
Real Estate [Member] | Non-Owner Occupied CRE [Member]        
Financing Receivable, Allowance for Credit Losses [Line Items]        
Beginning balance 13,869 15,709 14,561 14,664
Provision for loan losses (447) [1] (1,456) [1] (1,153) [2] (414) [2]
Charge-offs 0 (250) 0 (250)
Recoveries 14 5 28 8
Ending balance 13,436 14,008 13,436 14,008
Real Estate [Member] | Owner Occupied CRE [Member]        
Financing Receivable, Allowance for Credit Losses [Line Items]        
Beginning balance 24,336 21,492 25,368 21,413
Provision for loan losses (2,207) [1] (239) [1] (3,092) [2] (287) [2]
Charge-offs 0 0 (150) (175)
Recoveries 1,001 5 1,004 307
Ending balance 23,130 21,258 23,130 21,258
Real Estate [Member] | Residential [Member]        
Financing Receivable, Allowance for Credit Losses [Line Items]        
Beginning balance 25,944 21,739 25,614 20,488
Provision for loan losses 7,400 [1] (130) [1] 7,849 [2] 1,368 [2]
Charge-offs (364) (154) (504) (404)
Recoveries 23 22 44 25
Ending balance 33,003 21,477 33,003 21,477
Consumer [Member] | Auto [Member]        
Financing Receivable, Allowance for Credit Losses [Line Items]        
Beginning balance 1,856 1,495 1,598 1,186
Provision for loan losses 154 [1] 199 [1] 655 [2] 649 [2]
Charge-offs (160) (277) (518) (616)
Recoveries 127 129 242 327
Ending balance 1,977 1,546 1,977 1,546
Consumer [Member] | Non-Auto [Member]        
Financing Receivable, Allowance for Credit Losses [Line Items]        
Beginning balance 505 493 662 553
Provision for loan losses 67 [1] (13) [1] 65 [2] (56) [2]
Charge-offs (94) (148) (320) (239)
Recoveries 89 168 160 242
Ending balance $ 567 $ 500 $ 567 $ 500
[1] For the three-months ended June 30, 2026 and 2025, the provision for credit losses of $4,183,000 and $3,132,000, respectively, on the consolidated statements of earnings includes a provision for credit losses on loans of $3,915,000 and $2,432,000, respectively, and a provision for off-balance sheet unfunded commitments of $268,000 and $700,000, respectively.
[2] For the six-months ended June 30, 2026 and 2025, the provision for credit losses of $6,474,000 and $6,660,000, respectively, on the consolidated statements of earnings includes a provision for credit losses on loans of $6,653,000 and $5,423,000, respectively, and a provision reversal for off-balance sheet unfunded commitments of $179,000, and provision for off-balance sheet unfunded commitments of $1,237,000, respectively.