Derivatives and Hedging Activities - Additional Information (Detail)	3 Months Ended		6 Months Ended
	Jun. 30, 2025 USD ($) Derivative	Jun. 30, 2024 USD ($)	Jun. 30, 2025 USD ($) Derivative	Jun. 30, 2024 USD ($)	Dec. 31, 2024 USD ($) Derivative
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Collateral posted with market value on liability positions with credit risk-related contingent features	$ 4,800		$ 4,800		$ 42,600
Interest Rate Swaps and Caps [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Number of interest rate swaps | Derivative	325		325		293
Aggregate notional amount	$ 2,100,000,000		$ 2,100,000,000		$ 1,900,000,000
Income (loss) on derivative instrument not designated hedges	$ 1,400,000	$ 1,800,000	$ 3,400,000	$ 2,500,000
Risk Participation in Agreements [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Number of interest rate swaps | Derivative	29		29		24
Aggregate notional amount	$ 279,200,000		$ 279,200,000		$ 233,800,000
Risk Participation out Agreement [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Number of interest rate swaps | Derivative	8		8		8
Aggregate notional amount	$ 67,300,000		$ 67,300,000		$ 67,700,000
Other Contract [Member] | Forward TBA Contracts [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Aggregate notional amount	$ 173,000,000		$ 173,000,000		$ 29,000,000