v3.26.1
Goodwill and Other Intangibles - Changes In Intangible Assets (Detail) - USD ($)
$ in Thousands
Jun. 30, 2026
Dec. 31, 2025
Finite Lived Intangible Assets [Line Items]    
Gross carrying amount $ 605,379 $ 605,379
Accumulated amortization 165,430 118,510
Net carrying amount 439,949 486,869
Core Deposit Intangible Assets [Member]    
Finite Lived Intangible Assets [Line Items]    
Gross carrying amount 481,294 481,294
Accumulated amortization 120,819 81,203
Net carrying amount 360,475 400,091
Customer Relationships [Member]    
Finite Lived Intangible Assets [Line Items]    
Gross carrying amount 124,085 124,085
Accumulated amortization 44,611 37,307
Net carrying amount $ 79,474 $ 86,778