v3.26.3
Intangible Assets - Summary of Intangible Assets (Detail) - USD ($)
$ in Thousands
Sep. 30, 2026
Dec. 31, 2025
Finite-Lived Intangible Assets [Line Items]    
Goodwill not subject to amortization $ 2,018,848 $ 2,018,848
Core Deposit Intangible Assets [Member]    
Finite-Lived Intangible Assets [Line Items]    
Gross Carrying Amount 137,929 137,929
Accumulated Amortization (111,176) (105,662)
Community Banking [Member]    
Finite-Lived Intangible Assets [Line Items]    
Goodwill not subject to amortization 2,018,848 2,018,848
Community Banking [Member] | Core Deposit Intangible Assets [Member]    
Finite-Lived Intangible Assets [Line Items]    
Gross Carrying Amount 137,929 137,929
Accumulated Amortization $ (111,176) $ (105,662)