Fair Values of Assets and Liabilities - Summary of Significant Unobservable Inputs used in Level 3 Assets Measured at Fair Value on Recurring Basis (Detail) - Fair Value, Inputs, Level 3 [Member] - Fair Value, Measurements, Recurring [Member] $ in Thousands		12 Months Ended
		Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Mortgage servicing rights [Member]
Mortgage Servicing Rights	[1]	$ 357	$ 322	$ 273
Prepayment Rate [Member] | Minimum [Member]
Mortgage Servicing Rights, Measuring Inputs		0.0648	0.0663
Prepayment Rate [Member] | Maximum [Member]
Mortgage Servicing Rights, Measuring Inputs		0.2349	0.2556
Prepayment Rate [Member] | Weighted Average [Member]
Mortgage Servicing Rights, Measuring Inputs	[2]	0.0778	0.1339
Mortgage Servicing Rights		Prepayment Rate	Prepayment Rate
Prepayment Rate [Member] | Mortgage servicing rights [Member]
Servicing Asset, Valuation Technique [Extensible List]		us-gaap:ValuationTechniqueDiscountedCashFlowMember	us-gaap:ValuationTechniqueDiscountedCashFlowMember
Mortgage Servicing Rights		$ 357	$ 322
Discount Rate [Member] | Minimum [Member]
Mortgage Servicing Rights, Measuring Inputs		0.0950	0.0900
Discount Rate [Member] | Maximum [Member]
Mortgage Servicing Rights, Measuring Inputs		0.0950	0.0900
Discount Rate [Member] | Weighted Average [Member]
Mortgage Servicing Rights, Measuring Inputs	[2]	0.0950	0.0900
Mortgage Servicing Rights		Discount Rate	Discount Rate
Delinquency Rate [Member] | Minimum [Member]
Mortgage Servicing Rights, Measuring Inputs		0.0213	0.0282
Delinquency Rate [Member] | Maximum [Member]
Mortgage Servicing Rights, Measuring Inputs		0.0279	0.0363
Delinquency Rate [Member] | Weighted Average [Member]
Mortgage Servicing Rights, Measuring Inputs	[2]	0.0224	0.0296
Mortgage Servicing Rights		Delinquency Rate	Delinquency Rate
Default Rate [Member] | Minimum [Member]
Mortgage Servicing Rights, Measuring Inputs		0.0014	0.0008
Default Rate [Member] | Maximum [Member]
Mortgage Servicing Rights, Measuring Inputs		0.0020	0.0014
Default Rate [Member] | Weighted Average [Member]
Mortgage Servicing Rights, Measuring Inputs	[2]	0.0015	0.0013
Mortgage Servicing Rights		Default Rate	Default Rate

[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 (loss) income.

[2] Unobservable inputs for mortgage servicing rights were weighted by loan amount.