v3.26.3
Loans and the Allowance for Credit Losses - Summary of Changes in ACL (Detail) - USD ($)
$ in Thousands
 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Financing Receivable, Allowance for Credit Losses [Line Items]    
Allowance for credit losses - loans, beginning balance $ 218,749 $ 138,766
Allowance for credit losses - loan commitments, beginning balance 6,950 6,120
Total beginning allowance for credit losses - loans and loan commitments 225,699 144,886
Initial allowance for credit losses on acquired PCD loans   22,226
Provision for loan losses 14,665 72,641
Provision for loan commitments 2,284 1,508
Total provision for credit losses - loans and loan commitments 16,949 74,149
Charge-offs (26,546) (20,952)
Recoveries 7,690 4,985
Net (charge-offs) recoveries (18,856) (15,967)
Allowance for credit losses - loans, ending balance 214,558 217,666
Allowance for credit losses - loan commitments, ending balance 9,234 7,628
Total ending allowance for credit losses - loans and loan commitments 223,792 225,294
Commercial and Industrial [Member]    
Financing Receivable, Allowance for Credit Losses [Line Items]    
Allowance for credit losses - loans, beginning balance 64,932 42,398
Allowance for credit losses - loan commitments, beginning balance 552  
Total beginning allowance for credit losses - loans and loan commitments 65,484 42,398
Initial allowance for credit losses on acquired PCD loans   7,160
Provision for loan losses 14,354 19,172
Provision for loan commitments 26 (1,434)
Total provision for credit losses - loans and loan commitments 14,380 20,606
Charge-offs (15,229) (5,967)
Recoveries 3,340 1,568
Net (charge-offs) recoveries (11,889) (4,399)
Allowance for credit losses - loans, ending balance 67,397 64,331
Allowance for credit losses - loan commitments, ending balance 578 1,434
Total ending allowance for credit losses - loans and loan commitments 67,975 65,765
Deposit Overdraft [Member]    
Financing Receivable, Allowance for Credit Losses [Line Items]    
Allowance for credit losses - loans, beginning balance 1,855 1,713
Total beginning allowance for credit losses - loans and loan commitments 1,855 1,713
Provision for loan losses 1,001 1,887
Total provision for credit losses - loans and loan commitments 1,001 1,887
Charge-offs (1,484) (2,021)
Recoveries 446 555
Net (charge-offs) recoveries (1,038) (1,466)
Allowance for credit losses - loans, ending balance 1,818 2,134
Total ending allowance for credit losses - loans and loan commitments 1,818 2,134
Commercial Real Estate [Member] | Commercial Real Estate - Land and Construction [Member]    
Financing Receivable, Allowance for Credit Losses [Line Items]    
Allowance for credit losses - loans, beginning balance 10,707 8,411
Allowance for credit losses - loan commitments, beginning balance 5,499 5,105
Total beginning allowance for credit losses - loans and loan commitments 16,206 13,516
Initial allowance for credit losses on acquired PCD loans   177
Provision for loan losses (1,016) 1,865
Provision for loan commitments 1,767 146
Total provision for credit losses - loans and loan commitments 751 2,011
Recoveries 513 15
Net (charge-offs) recoveries 513 15
Allowance for credit losses - loans, ending balance 10,204 10,468
Allowance for credit losses - loan commitments, ending balance 7,266 5,251
Total ending allowance for credit losses - loans and loan commitments 17,470 15,719
Commercial Real Estate [Member] | Commercial Real Estate - Improved Property [Member]    
Financing Receivable, Allowance for Credit Losses [Line Items]    
Allowance for credit losses - loans, beginning balance 96,714 59,828
Total beginning allowance for credit losses - loans and loan commitments 96,714 59,828
Initial allowance for credit losses on acquired PCD loans   7,998
Provision for loan losses (1,462) 32,212
Provision for loan commitments 263  
Total provision for credit losses - loans and loan commitments (1,199) 32,212
Charge-offs (980) (4,498)
Recoveries 193 339
Net (charge-offs) recoveries (787) (4,159)
Allowance for credit losses - loans, ending balance 94,465 95,879
Allowance for credit losses - loan commitments, ending balance 263  
Total ending allowance for credit losses - loans and loan commitments 94,728 95,879
Residential Real Estate [Member]    
Financing Receivable, Allowance for Credit Losses [Line Items]    
Allowance for credit losses - loans, beginning balance 33,416 21,790
Allowance for credit losses - loan commitments, beginning balance 890 1,015
Total beginning allowance for credit losses - loans and loan commitments 34,306 22,805
Initial allowance for credit losses on acquired PCD loans   3,192
Provision for loan losses 601 8,536
Provision for loan commitments 217 (82)
Total provision for credit losses - loans and loan commitments 818 8,454
Charge-offs (2,143) (862)
Recoveries 429 349
Net (charge-offs) recoveries (1,714) (513)
Allowance for credit losses - loans, ending balance 32,303 33,005
Allowance for credit losses - loan commitments, ending balance 1,107 933
Total ending allowance for credit losses - loans and loan commitments 33,410 33,938
Consumer [Member]    
Financing Receivable, Allowance for Credit Losses [Line Items]    
Allowance for credit losses - loans, beginning balance 8,742 3,391
Allowance for credit losses - loan commitments, beginning balance 9  
Total beginning allowance for credit losses - loans and loan commitments 8,751 3,391
Initial allowance for credit losses on acquired PCD loans   3,095
Provision for loan losses 216 7,598
Provision for loan commitments 11 10
Total provision for credit losses - loans and loan commitments 227 7,608
Charge-offs (5,445) (6,333)
Recoveries 2,474 1,850
Net (charge-offs) recoveries (2,971) (4,483)
Allowance for credit losses - loans, ending balance 5,987 9,601
Allowance for credit losses - loan commitments, ending balance 20 10
Total ending allowance for credit losses - loans and loan commitments 6,007 9,611
Home Equity [Member]    
Financing Receivable, Allowance for Credit Losses [Line Items]    
Allowance for credit losses - loans, beginning balance 2,383 1,235
Total beginning allowance for credit losses - loans and loan commitments 2,383 1,235
Initial allowance for credit losses on acquired PCD loans   604
Provision for loan losses 971 1,371
Total provision for credit losses - loans and loan commitments 971 1,371
Charge-offs (1,265) (1,271)
Recoveries 295 309
Net (charge-offs) recoveries (970) (962)
Allowance for credit losses - loans, ending balance 2,384 2,248
Total ending allowance for credit losses - loans and loan commitments $ 2,384 $ 2,248