Federal Home Loan Bank Advances and Other Borrowings - Additional Information (Detail) - USD ($)	12 Months Ended
Jun. 30, 2025	Jun. 30, 2024
Federal Reserve Bank, Advances [Line Items]
Long-Term Advances	$ 0
Short-Term Advances		$ 0
Long-Term Federal Home Loan Bank Advances, Total	$ 10,350,000	$ 10,350,000
Weighted average rate, long term		4.51%
General debt obligations, Disclosures, Description of collateral pledged	All borrowings from the FHLB are secured by a blanket lien on qualified collateral, defined principally as first mortgage loans on owner-occupied one- to four-family residential properties.
Federal reserve bank stock	$ 0	$ 0
Overnight Advances [Member]
Federal Reserve Bank, Advances [Line Items]
Short-Term Advances	0	0
Line of Credit [Member]
Federal Reserve Bank, Advances [Line Items]
Long-Term Federal Home Loan Bank Advances, Total	$ 10,400,000	10,400,000
Weighted average rate, long term	4.51%
Debt instrument, Basis spread on Variable rate	0.50%
Security Owned and Pledged as Collateral, Fair Values	$ 28,777,000	28,478,000
Federal Home Loan Bank of Boston [Member] \| Line of Credit [Member]
Federal Reserve Bank, Advances [Line Items]
Advances, general debt obligations, Maximum amount available	$ 2,354,000
Branch of FHLB bank, Interest rate, Terms	interest rate that adjusts daily
Branch of FHLB bank, Percentage of the banks total asset that can be borrowed	2.00%
Branch of FHLB bank, Amount of advances	$ 0	$ 0

Federal home loan bank advances branch of fhlb bank interest rate terms.

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Federal home loan bank advances branch of fhlb bank percentage of the banks total asset that can be borrowed.

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Federal Home Loan Bank, Long Term Advances

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Federal Home Loan Bank, Short Term Advances

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Security Owned and Pledged as Collateral, Fair Values

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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The calculated weighted average interest rate for Federal Home Loan Bank advances for the period ended as of the Balance Sheet date.

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Amount of advance from Federal Home Loan Bank (FHLBank).

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- Definition

Describes the collateral pledged in support of Federal Home Loan Bank advances outstanding as of the Balance Sheet date.

+ References

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-Topic 942
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Amount of maximum advances or credit lines available from the Federal Home Loan Bank (FHLB).

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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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Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

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Federal Reserve Bank stock represents an equity interest in the Federal Reserve Bank. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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