v3.26.3
Fair Value Information - Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($)
$ in Thousands
Sep. 30, 2026
Dec. 31, 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment securities available-for-sale $ 3,527,833 $ 2,683,070
Interest rate swaps, assets 55,536 [1] 161
Interest rate swaps, liabilities 603,614 [2] 502,031
Municipal Bonds [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment securities available-for-sale 19,585 21,290
Carrying Value [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment securities available-for-sale 3,527,833 2,683,070
Carrying Value [Member] | Interest Rate Swaps [Member] | Not Designated as Hedging Instrument [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Interest rate swaps, assets 31,674 161
Interest rate swaps, liabilities 31,674 161
Carrying Value [Member] | Fair Value Hedges [Member] | Interest Rate Swaps [Member] | Designated as Hedging Instrument [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Interest rate swaps, assets 23,774  
Interest rate swaps, liabilities   8,650
Carrying Value [Member] | Cash flow hedges [Member] | Interest Rate Swaps [Member] | Designated as Hedging Instrument [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Interest rate swaps, assets 88  
Interest rate swaps, liabilities 56 2,619
Fair Value on Recurring Basis [Member] | Level 1 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Equity securities 14,570  
Total assets 14,570 0
Total liabilities 0 0
Fair Value on Recurring Basis [Member] | Level 2 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total assets 3,583,369 2,683,231
Total liabilities 31,730 11,430
Fair Value on Recurring Basis [Member] | Level 3 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total assets 0 0
Total liabilities 0 0
Fair Value on Recurring Basis [Member] | Municipal Bonds [Member] | Level 1 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment securities available-for-sale 0 0
Fair Value on Recurring Basis [Member] | Municipal Bonds [Member] | Level 2 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment securities available-for-sale 19,585 21,290
Fair Value on Recurring Basis [Member] | Municipal Bonds [Member] | Level 3 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment securities available-for-sale 0 0
Fair Value on Recurring Basis [Member] | Government agency/GSE [Member] | Level 1 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment securities available-for-sale 0 0
Fair Value on Recurring Basis [Member] | Government agency/GSE [Member] | Level 2 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment securities available-for-sale 45,449 35,284
Fair Value on Recurring Basis [Member] | Government agency/GSE [Member] | Level 3 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment securities available-for-sale 0 0
Fair Value on Recurring Basis [Member] | Mortgage-backed Securities [Member] | Level 1 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment securities available-for-sale 0 0
Fair Value on Recurring Basis [Member] | Mortgage-backed Securities [Member] | Level 2 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment securities available-for-sale 2,493,391 1,887,654
Fair Value on Recurring Basis [Member] | Mortgage-backed Securities [Member] | Level 3 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment securities available-for-sale 0 0
Fair Value on Recurring Basis [Member] | CMO/REMIC [Member] | Level 1 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment securities available-for-sale 0 0
Fair Value on Recurring Basis [Member] | CMO/REMIC [Member] | Level 2 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment securities available-for-sale 925,384 695,150
Fair Value on Recurring Basis [Member] | CMO/REMIC [Member] | Level 3 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment securities available-for-sale 0 0
Fair Value on Recurring Basis [Member] | Collateralized Loan Obligations [Member] | Level 2 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment securities available-for-sale 42,048 42,000
Fair Value on Recurring Basis [Member] | Other Securities [Member] | Level 1 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment securities available-for-sale 0 0
Fair Value on Recurring Basis [Member] | Other Securities [Member] | Level 2 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment securities available-for-sale 1,976 1,692
Fair Value on Recurring Basis [Member] | Other Securities [Member] | Level 3 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment securities available-for-sale 0 0
Fair Value on Recurring Basis [Member] | Investment Securities-AFS [Member] | Level 1 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment securities available-for-sale 0 0
Fair Value on Recurring Basis [Member] | Investment Securities-AFS [Member] | Level 2 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment securities available-for-sale 3,527,833 2,683,070
Fair Value on Recurring Basis [Member] | Investment Securities-AFS [Member] | Level 3 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment securities available-for-sale 0 0
Fair Value on Recurring Basis [Member] | Interest Rate Swaps [Member] | Not Designated as Hedging Instrument [Member] | Level 1 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Interest rate swaps, assets 0 0
Interest rate swaps, liabilities 0 0
Fair Value on Recurring Basis [Member] | Interest Rate Swaps [Member] | Not Designated as Hedging Instrument [Member] | Level 2 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Interest rate swaps, assets 31,674 161
Interest rate swaps, liabilities 31,674 161
Fair Value on Recurring Basis [Member] | Interest Rate Swaps [Member] | Not Designated as Hedging Instrument [Member] | Level 3 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Interest rate swaps, assets 0 0
Interest rate swaps, liabilities 0 0
Fair Value on Recurring Basis [Member] | Interest Rate Swaps [Member] | Designated as Hedging Instrument [Member] | Level 1 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Interest rate swaps, assets   0
Fair Value on Recurring Basis [Member] | Interest Rate Swaps [Member] | Designated as Hedging Instrument [Member] | Level 2 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Interest rate swaps, assets   8,650
Fair Value on Recurring Basis [Member] | Interest Rate Swaps [Member] | Designated as Hedging Instrument [Member] | Level 3 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Interest rate swaps, assets   0
Fair Value on Recurring Basis [Member] | Fair Value Hedges [Member] | Interest Rate Swaps [Member] | Designated as Hedging Instrument [Member] | Level 1 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Interest rate swaps, assets 0  
Fair Value on Recurring Basis [Member] | Fair Value Hedges [Member] | Interest Rate Swaps [Member] | Designated as Hedging Instrument [Member] | Level 2 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Interest rate swaps, assets 23,774  
Fair Value on Recurring Basis [Member] | Fair Value Hedges [Member] | Interest Rate Swaps [Member] | Designated as Hedging Instrument [Member] | Level 3 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Interest rate swaps, assets 0  
Fair Value on Recurring Basis [Member] | Cash flow hedges [Member] | Interest Rate Swaps [Member] | Designated as Hedging Instrument [Member] | Level 1 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Interest rate swaps, assets 0  
Interest rate swaps, liabilities 0 0
Fair Value on Recurring Basis [Member] | Cash flow hedges [Member] | Interest Rate Swaps [Member] | Designated as Hedging Instrument [Member] | Level 2 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Interest rate swaps, assets 88  
Interest rate swaps, liabilities 56 2,619
Fair Value on Recurring Basis [Member] | Cash flow hedges [Member] | Interest Rate Swaps [Member] | Designated as Hedging Instrument [Member] | Level 3 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Interest rate swaps, liabilities   0
Fair Value on Recurring Basis [Member] | Carrying Value [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Equity securities 14,570  
Total assets 3,597,939 2,683,231
Total liabilities 31,730 11,430
Fair Value on Recurring Basis [Member] | Carrying Value [Member] | Municipal Bonds [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment securities available-for-sale 19,585 21,290
Fair Value on Recurring Basis [Member] | Carrying Value [Member] | Government agency/GSE [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment securities available-for-sale 45,449 35,284
Fair Value on Recurring Basis [Member] | Carrying Value [Member] | Mortgage-backed Securities [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment securities available-for-sale 2,493,391 1,887,654
Fair Value on Recurring Basis [Member] | Carrying Value [Member] | CMO/REMIC [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment securities available-for-sale 925,384 695,150
Fair Value on Recurring Basis [Member] | Carrying Value [Member] | Collateralized Loan Obligations [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment securities available-for-sale 42,048 42,000
Fair Value on Recurring Basis [Member] | Carrying Value [Member] | Other Securities [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment securities available-for-sale 1,976 1,692
Fair Value on Recurring Basis [Member] | Carrying Value [Member] | Investment Securities-AFS [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment securities available-for-sale 3,527,833 2,683,070
Fair Value on Recurring Basis [Member] | Carrying Value [Member] | Interest Rate Swaps [Member] | Not Designated as Hedging Instrument [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Interest rate swaps, assets 31,674 161
Interest rate swaps, liabilities 31,674 161
Fair Value on Recurring Basis [Member] | Carrying Value [Member] | Fair Value Hedges [Member] | Interest Rate Swaps [Member] | Designated as Hedging Instrument [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Interest rate swaps, assets 23,774 8,650
Fair Value on Recurring Basis [Member] | Carrying Value [Member] | Cash flow hedges [Member] | Interest Rate Swaps [Member] | Designated as Hedging Instrument [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Interest rate swaps, assets 88  
Interest rate swaps, liabilities $ 56 $ 2,619
[1] Represents cash collateral received from or pledged with counterparty bank.
[2] Represents the fair value of securities pledged with counterparty bank. Amounts are limited to the derivative asset or liability balance and, accordingly, do not include excess collateral, if any, received or pledged.