Mortgage Servicing Rights - Additional Information (Detail) - USD ($)	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Risks Inherent in Servicing Assets and Servicing Liabilities [Line Items]
Unpaid principal balance of mortgage loans serviced for others	$ 282,200,000	$ 304,300,000
Mortgage servicing rights , valuation allowance	$ 0	$ 0
Minimum [Member]
Risks Inherent in Servicing Assets and Servicing Liabilities [Line Items]
Discount rates used in valuation model	10.10%	10.00%
Prepayment speeds used in valuation model	6.90%	7.00%
Maximum [Member]
Risks Inherent in Servicing Assets and Servicing Liabilities [Line Items]
Discount rates used in valuation model	13.00%	13.00%
Prepayment speeds used in valuation model	34.40%	33.90%

Unpaid Principal Balance of Loans Serviced for Others

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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.

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481229/860-50-50-2

+ Details

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- Definition

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

+ References

+ Details

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- Definition

Reflects the estimated amount of impairment as of the balance sheet date of recognized servicing assets that are being amortized in proportion to and over the period of estimated net servicing income or loss.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (e)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481229/860-50-50-4

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