v3.26.1
Allowance for Credit Losses - Schedule of Allowance for Loan Losses and Carrying Amount of Loans (Detail) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended 12 Months Ended
Jun. 30, 2026
Jun. 30, 2026
Dec. 31, 2025
Financing Receivable, Allowance for Credit Losses [Line Items]      
Allowance for Loan and Lease Losses Beginning balance $ 299,599 $ 297,518 $ 271,844
Initial allowance for PCD loans (acquired during the period)     17,518
Charge-offs (6,113) (12,943) (50,912)
Recoveries 1,055 2,190 5,200
Provision 4,963 12,739 53,868
Allowance for Loan and Lease Losses Ending balance 299,504 299,504 297,518
Construction & Land Development [Member]      
Financing Receivable, Allowance for Credit Losses [Line Items]      
Allowance for Loan and Lease Losses Beginning balance 53,877 57,967 63,621
Initial allowance for PCD loans (acquired during the period)     4,584
Charge-offs 0 0 (408)
Recoveries 352 352 225
Provision (2,909) (6,999) (10,055)
Allowance for Loan and Lease Losses Ending balance 51,320 51,320 57,967
Bank Card [Member]      
Financing Receivable, Allowance for Credit Losses [Line Items]      
Allowance for Loan and Lease Losses Beginning balance 943 889 891
Initial allowance for PCD loans (acquired during the period)     0
Charge-offs (54) (115) (320)
Recoveries 15 20 55
Provision 125 235 263
Allowance for Loan and Lease Losses Ending balance 1,029 1,029 889
Commercial Real Estate [Member] | Owner-Occupied [Member]      
Financing Receivable, Allowance for Credit Losses [Line Items]      
Allowance for Loan and Lease Losses Beginning balance 13,643 13,564 11,852
Initial allowance for PCD loans (acquired during the period)     795
Charge-offs 0 0 (228)
Recoveries 219 235 318
Provision (109) (46) 827
Allowance for Loan and Lease Losses Ending balance 13,753 13,753 13,564
Commercial Real Estate [Member] | Nonowner-Occupied [Member]      
Financing Receivable, Allowance for Credit Losses [Line Items]      
Allowance for Loan and Lease Losses Beginning balance 101,745 96,716 74,522
Initial allowance for PCD loans (acquired during the period)     11,059
Charge-offs (1,054) (4,918) (35,798)
Recoveries 73 74 160
Provision 6,838 15,730 46,773
Allowance for Loan and Lease Losses Ending balance 107,602 107,602 96,716
Other Commercial [Member]      
Financing Receivable, Allowance for Credit Losses [Line Items]      
Allowance for Loan and Lease Losses Beginning balance 62,373 61,729 65,105
Initial allowance for PCD loans (acquired during the period)     872
Charge-offs (4,142) (5,576) (5,424)
Recoveries 121 699 2,309
Provision 324 1,824 (1,133)
Allowance for Loan and Lease Losses Ending balance 58,676 58,676 61,729
Residential Real Estate [Member]      
Financing Receivable, Allowance for Credit Losses [Line Items]      
Allowance for Loan and Lease Losses Beginning balance 53,630 53,949 46,373
Initial allowance for PCD loans (acquired during the period)     208
Charge-offs 0 (275) (999)
Recoveries 35 86 704
Provision (93) (188) 7,663
Allowance for Loan and Lease Losses Ending balance 53,572 53,572 53,949
Other Consumer [Member]      
Financing Receivable, Allowance for Credit Losses [Line Items]      
Allowance for Loan and Lease Losses Beginning balance 13,388 12,704 9,480
Initial allowance for PCD loans (acquired during the period)     0
Charge-offs (863) (2,059) (7,735)
Recoveries 240 724 1,429
Provision 787 2,183 9,530
Allowance for Loan and Lease Losses Ending balance $ 13,552 $ 13,552 $ 12,704