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Fair Values of Assets and Liabilities - Summary of Changes in Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis (Detail) - Fair Value, Inputs, Level 3 [Member] - Fair Value, Measurements, Recurring [Member] - Mortgage servicing rights [Member] - USD ($) $ in Thousands		9 Months Ended
		Sep. 30, 2025	Sep. 30, 2024
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	[1]	$ 305	$ 339
Included in net income (loss)	[1]	(38)	(31)
Ending Balance	[1]	$ 267	$ 308
[1] Realized and unrealized gains and losses related to mortgage servicing rights are reported as a component of loan servicing fee income in the Company’s consolidated statements of income (loss).

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