v3.26.3
Derivatives and Hedging Activities - Summary of Fair Values of Derivative Instruments on Balance Sheets (Detail) - USD ($)
Sep. 30, 2026
Dec. 31, 2025
Derivatives, Fair Value [Line Items]    
Asset Derivatives $ 100,397,000 $ 63,836,000
Derivative Asset, Statement of Financial Position [Extensible Enumeration] Other Assets Other Assets
Liability Derivatives $ 97,876,000 $ 64,394,000
Derivative Liability, Statement of Financial Position [Extensible Enumeration] Other Liabilities Other Liabilities
Interest Rate Swaps and Caps [Member] | Loan Swaps [Member]    
Derivatives, Fair Value [Line Items]    
Notional or Contractual Amount $ 2,779,418,000 $ 2,612,677,000
Asset Derivatives 99,078,000 63,144,000
Liability Derivatives 97,876,000 64,181,000
Interest Rate Lock Commitments [Member] | Other Contract [Member]    
Derivatives, Fair Value [Line Items]    
Notional or Contractual Amount 20,962,000 27,615,000
Asset Derivatives 237,000 692,000
Liability Derivatives 0 0
Forward TBA Contracts [Member] | Other Contract [Member]    
Derivatives, Fair Value [Line Items]    
Notional or Contractual Amount 46,500,000 91,000,000
Asset Derivatives 1,082,000 0
Liability Derivatives $ 0 $ 213,000