Fair Value - Undesignated Derivative Instruments (Detail) - Mortgage Banking - Level 2 - Fair Value, Recurring - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Other Assets \| Rate Lock Commitments
Derivatives, Fair Value [Line Items]
Gross assets	$ 38,740	$ 34,935
Gross liabilities	1,098	25,739
Net rate lock commitments and forward sales contracts	37,642	9,196
Accrued Liabilities \| Forward Sales Contracts
Derivatives, Fair Value [Line Items]
Gross assets	1,734	6,822
Gross liabilities	3,728	1,122
Net rate lock commitments and forward sales contracts	$ (1,994)	$ 5,700

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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