Mortgage Servicing Rights - Additional Information (Detail) - USD ($)	3 Months Ended	12 Months Ended
Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Servicing Assets at Fair Value [Line Items]
Estimated fair value of mortgage servicing rights	$ 4,241,000		$ 4,554,000
Temporary impairment charge of mortgage servicing rights	0	$ 0
Mortgage Servicing Rights [Member]
Servicing Assets at Fair Value [Line Items]
Loans serviced for others unpaid principal balance	$ 1,173,246		$ 1,202,448
Net servicing fee percentage	0.25%		0.25%
Mortgage Servicing Rights [Member] \| Minimum [Member]
Servicing Assets at Fair Value [Line Items]
Discount rate used in estimating the fair value of servicing rights	10.19%		10.50%
Weighted average prepayment rates used in estimating the fair value of servicing rights	10.59%		10.58%
Deliquency rate used in determning fair value of servicing rights	7.62%		7.84%
Mortgage Servicing Rights [Member] \| Maximum [Member]
Servicing Assets at Fair Value [Line Items]
Discount rate used in estimating the fair value of servicing rights	11.15%		10.82%
Weighted average prepayment rates used in estimating the fair value of servicing rights	9.16%		9.43%
Deliquency rate used in determning fair value of servicing rights	9.96%		10.25%
Mortgage Servicing Rights [Member] \| Weighted Average [Member] \| Including Loans On Forbearance [Member]
Servicing Assets at Fair Value [Line Items]
Deliquency rate used in determning fair value of servicing rights	2.65%		3.29%
Mortgage Servicing Rights [Member] \| Loan Origination Commitments [Member] \| Median [Member]
Servicing Assets at Fair Value [Line Items]
Estimated fair value of mortgage servicing rights	$ 13,439		$ 13,427

The unpaid principal balance on loans serviced for others.

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- Definition

The servicing fee as a percentage of each mortgage payment made by a borrower to a mortgage servicer as compensation for keeping a record of payments, collecting, and making escrow payments, passing principal and interest payments along to the note holder.

+ References

No definition available.

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- Definition

Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

+ References

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- Definition

Discount rate used to estimate the fair value of servicing assets and servicing liabilities.

+ References

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- Definition

Percentage of contractually collectible principal associated with a financial asset expected not to be collected due to default by the borrower.

+ References

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- Definition

Estimated rate of prepayments of principal on servicing assets and servicing liabilities.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

The net increase (decrease) in the valuation allowance for servicing assets subsequently measured using the amortization method.

+ References

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