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Borrowings - Schedule of Federal Home Loan Bank Advances by Branch of FHLB Bank (Detail) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Principal Amounts	$ 51,748	$ 52,268
Federal Home Loan Bank Advances One [Member]
Principal Amounts	$ 50,000	$ 520
Maturity Dates	2026	2025
Interest Rates		0.00%
Federal Home Loan Bank Advances One [Member] | Minimum [Member]
Interest Rates	4.38%
Federal Home Loan Bank Advances One [Member] | Maximum [Member]
Interest Rates	4.48%
Federal Home Loan Bank Advances Two [Member]
Principal Amounts	$ 718	$ 50,000
Maturity Dates	2028	2026
Interest Rates	0.00%
Federal Home Loan Bank Advances Two [Member] | Minimum [Member]
Interest Rates		4.38%
Federal Home Loan Bank Advances Two [Member] | Maximum [Member]
Interest Rates		4.48%
Federal Home Loan Bank Advances Three [Member]
Principal Amounts	$ 400	$ 718
Maturity Dates	2029	2028
Interest Rates	0.00%	0.00%
Federal Home Loan Bank Advances Four [Member]
Principal Amounts	$ 200	$ 400
Maturity Dates	2030	2029
Interest Rates	0.00%	0.00%
Federal Home Loan Bank Advances Five [Member]
Principal Amounts	$ 430	$ 200
Maturity Dates	2031	2030
Interest Rates	0.00%	0.00%
Federal Home Loan Bank Advances Six [Member]
Principal Amounts		$ 430
Maturity Dates		2031
Interest Rates		0.00%

X

- Definition

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 470
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478878/942-470-45-1

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X

- Definition

The year of maturity, when only one maturity date applies, for the advances from the Federal Home Loan Bank as of the Balance Sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 470
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478878/942-470-45-1

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-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477734/942-470-50-3

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- Definition

States the interest rate applicable to Federal Home Loan Bank advances outstanding as of the Balance Sheet date.

+ References

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-Topic 942
-SubTopic 470
-Name Accounting Standards Codification
-Section 45
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