v3.25.2
Fair Value Information - Estimated Fair Value of Financial Instruments (Detail) - USD ($)
$ in Thousands
Jun. 30, 2025
Dec. 31, 2024
Assets    
Total cash and cash equivalents $ 738,636 $ 204,698
Investment securities available-for-sale 2,486,306 2,542,115
Investment securities held-to-maturity 2,327,230 2,379,668
Total loans, net of allowance for loan losses 8,280,498 8,456,310
Deposits:    
Interest-bearing 4,737,695 4,911,285
Interest Rate Swaps [Member]    
Assets    
Interest rate swaps, assets 188 7,252
Deposits:    
Interest rate swaps, liabilities 416,782 262,434
Derivatives Not Designated as Hedging Instruments [Member] | Interest Rate Swaps [Member]    
Assets    
Interest rate swaps, assets 188 30
Deposits:    
Interest rate swaps, liabilities 188 30
Fair Value Hedging [Member] | Interest Rate Swaps [Member]    
Assets    
Interest rate swaps, assets 7,222
Deposits:    
Interest rate swaps, liabilities 9,585 0
Cash Flow Hedging [Member] | Interest Rate Swaps [Member]    
Assets    
Interest rate swaps, assets  
Deposits:    
Interest rate swaps, liabilities 2,855 517
Carrying Value [Member]    
Assets    
Total cash and cash equivalents 738,636 204,698
Interest-earning balances due from depository institutions 11,004 480
Investment securities available-for-sale 2,486,306 2,542,115
Investment securities held-to-maturity 2,327,230 2,379,668
Total loans, net of allowance for loan losses 8,280,498 8,456,310
Deposits:    
Interest-bearing 4,737,695 4,911,285
Borrowings 904,154 761,887
Carrying Value [Member] | Derivatives Not Designated as Hedging Instruments [Member] | Interest Rate Swaps [Member]    
Assets    
Interest rate swaps, assets 188 30
Deposits:    
Interest rate swaps, liabilities 188 30
Carrying Value [Member] | Fair Value Hedging [Member] | Derivatives designated as hedging instruments [Member] | Interest Rate Swaps [Member]    
Assets    
Interest rate swaps, assets 0 7,222
Deposits:    
Interest rate swaps, liabilities 9,585 0
Carrying Value [Member] | Cash Flow Hedging [Member] | Derivatives designated as hedging instruments [Member] | Interest Rate Swaps [Member]    
Assets    
Interest rate swaps, assets 0 0
Deposits:    
Interest rate swaps, liabilities 2,855 517
Estimated Fair Value [Member]    
Assets    
Total cash and cash equivalents 738,636 204,698
Interest-earning balances due from depository institutions 11,004 480
Investment securities available-for-sale 2,486,306 2,542,115
Investment securities held-to-maturity 1,934,756 1,954,345
Total loans, net of allowance for loan losses 8,100,619 8,149,801
Deposits:    
Interest-bearing 4,734,567 4,908,070
Borrowings 871,106 716,566
Estimated Fair Value [Member] | Level 1 [Member]    
Assets    
Total cash and cash equivalents 738,636 204,698
Interest-earning balances due from depository institutions 0 0
Investment securities available-for-sale 0 0
Investment securities held-to-maturity 0 0
Total loans, net of allowance for loan losses 0 0
Deposits:    
Interest-bearing 0 0
Borrowings 0 0
Estimated Fair Value [Member] | Level 2 [Member]    
Assets    
Total cash and cash equivalents 0 0
Interest-earning balances due from depository institutions 11,004 480
Investment securities available-for-sale 2,486,306 2,542,115
Investment securities held-to-maturity 1,934,756 1,954,345
Total loans, net of allowance for loan losses 0 0
Deposits:    
Interest-bearing 4,734,567 4,908,070
Borrowings 871,106 716,566
Estimated Fair Value [Member] | Level 3 [Member]    
Assets    
Total cash and cash equivalents 0 0
Interest-earning balances due from depository institutions 0
Investment securities available-for-sale 0 0
Investment securities held-to-maturity 0 0
Total loans, net of allowance for loan losses 8,100,619 8,149,801
Deposits:    
Interest-bearing 0 0
Borrowings 0 0
Estimated Fair Value [Member] | Derivatives Not Designated as Hedging Instruments [Member] | Interest Rate Swaps [Member]    
Assets    
Interest rate swaps, assets 188 30
Deposits:    
Interest rate swaps, liabilities 188 30
Estimated Fair Value [Member] | Derivatives Not Designated as Hedging Instruments [Member] | Level 1 [Member] | Interest Rate Swaps [Member]    
Assets    
Interest rate swaps, assets 0 0
Deposits:    
Interest rate swaps, liabilities 0 0
Estimated Fair Value [Member] | Derivatives Not Designated as Hedging Instruments [Member] | Level 2 [Member] | Interest Rate Swaps [Member]    
Assets    
Interest rate swaps, assets 188 30
Deposits:    
Interest rate swaps, liabilities 188 30
Estimated Fair Value [Member] | Derivatives Not Designated as Hedging Instruments [Member] | Level 3 [Member] | Interest Rate Swaps [Member]    
Assets    
Interest rate swaps, assets 0 0
Deposits:    
Interest rate swaps, liabilities 0 0
Estimated Fair Value [Member] | Fair Value Hedging [Member] | Derivatives designated as hedging instruments [Member] | Interest Rate Swaps [Member]    
Assets    
Interest rate swaps, assets 0 7,222
Deposits:    
Interest rate swaps, liabilities 9,585 0
Estimated Fair Value [Member] | Fair Value Hedging [Member] | Derivatives designated as hedging instruments [Member] | Level 1 [Member] | Interest Rate Swaps [Member]    
Assets    
Interest rate swaps, assets 0 0
Deposits:    
Interest rate swaps, liabilities 0 0
Estimated Fair Value [Member] | Fair Value Hedging [Member] | Derivatives designated as hedging instruments [Member] | Level 2 [Member] | Interest Rate Swaps [Member]    
Assets    
Interest rate swaps, assets 0 7,222
Deposits:    
Interest rate swaps, liabilities 9,585 0
Estimated Fair Value [Member] | Fair Value Hedging [Member] | Derivatives designated as hedging instruments [Member] | Level 3 [Member] | Interest Rate Swaps [Member]    
Assets    
Interest rate swaps, assets 0 0
Deposits:    
Interest rate swaps, liabilities 0 0
Estimated Fair Value [Member] | Cash Flow Hedging [Member] | Derivatives designated as hedging instruments [Member] | Interest Rate Swaps [Member]    
Assets    
Interest rate swaps, assets 0 0
Deposits:    
Interest rate swaps, liabilities 2,855 517
Estimated Fair Value [Member] | Cash Flow Hedging [Member] | Derivatives designated as hedging instruments [Member] | Level 1 [Member] | Interest Rate Swaps [Member]    
Assets    
Interest rate swaps, assets 0 0
Deposits:    
Interest rate swaps, liabilities 0 0
Estimated Fair Value [Member] | Cash Flow Hedging [Member] | Derivatives designated as hedging instruments [Member] | Level 2 [Member] | Interest Rate Swaps [Member]    
Assets    
Interest rate swaps, assets 0 0
Deposits:    
Interest rate swaps, liabilities 2,855 517
Estimated Fair Value [Member] | Cash Flow Hedging [Member] | Derivatives designated as hedging instruments [Member] | Level 3 [Member] | Interest Rate Swaps [Member]    
Assets    
Interest rate swaps, assets 0 0
Deposits:    
Interest rate swaps, liabilities $ 0 $ 0