Disclosures About Fair Value of Assets - Estimated Fair Values of Financial Instruments and Level within Fair Value Hierarchy in which Fair Value Measurements Fall (Detail) - USD ($) $ in Thousands	Sep. 30, 2025	Jun. 30, 2025
Financial assets
Cash and cash equivalents	$ 8,027	$ 20,092
Interest-bearing time deposits in banks	250	250
Loans, net of allowance for credit losses	619,282	633,603
Federal Home Loan Bank stock	4,844	5,174
Accrued interest receivable	3,693	3,545
Financial liabilities
Deposits	680,264	721,258
Repurchase agreements	18,130	18,795
Federal Home Loan Bank advances	69,124	54,124
Advances from borrowers for taxes and insurance	681	972
Accrued interest payable	1,812	1,861
Unrecognized financial instruments (net of contract amount)
Commitments to originate loans	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Financial assets
Cash and cash equivalents	8,027	20,092
Interest-bearing time deposits in banks	250	250
Unrecognized financial instruments (net of contract amount)
Commitments to originate loans	0	0
Significant Other Observable Inputs (Level 2) [Member]
Financial assets
Federal Home Loan Bank stock	4,844	5,174
Accrued interest receivable	3,693	3,545
Financial liabilities
Deposits	361,787	408,173
Repurchase agreements	18,130	18,795
Federal Home Loan Bank advances	68,007	52,892
Advances from borrowers for taxes and insurance	681	972
Accrued interest payable	1,812	1,861
Unrecognized financial instruments (net of contract amount)
Commitments to originate loans	0	0
Significant Unobservable Inputs (Level 3) [Member]
Financial assets
Loans, net of allowance for credit losses	598,392	610,986
Financial liabilities
Deposits	318,241	312,719
Unrecognized financial instruments (net of contract amount)
Commitments to originate loans	$ 0	$ 0

Commitments to originate loans.

No definition available.

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- Definition

Interest-bearing time deposits in banks.

+ References

No definition available.

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- Definition

Interest bearing time deposits in banks.

+ References

No definition available.

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- Definition

Unrecognized financial instruments (net of contract amount).

+ References

No definition available.

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- Definition

Carrying amount of accumulated prepayments received by financial institutions from borrowers for taxes (for example, property taxes) and insurance (for example, property and catastrophe) which will periodically be remitted to the appropriate governmental agency or vendor on behalf of the borrower.

+ References

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- 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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- Definition

Amount of cash and cash equivalent. Cash includes, but is not limited to, currency on hand, demand deposit with financial institution, and account with general characteristic of demand deposit. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
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-Name Accounting Standards Codification
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- Definition

Fair value portion of arrangements with third parties, including, but not limited to, operating lease arrangement and arrangement in which the entity has agreed to expend funds to procure goods or services, or has agreed to commit resources to supply goods or services.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
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- Definition

The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

+ References

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
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-Name Accounting Standards Codification
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-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477974/942-325-45-1

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- References

No definition available.

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- References

No definition available.

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- Definition

Amortized cost excluding accrued interest, after allowance for credit loss, of financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
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-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

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- Definition

Amount of interest payable on debt, including, but not limited to, trade payables.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
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-Subparagraph (SX 210.9-03(15)(5))
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- Definition

Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
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-Subparagraph (SX 210.5-02(3)(a)(4))
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- Definition

Carrying value, as of the balance sheet date, of securities sold under agreements to repurchase where the transferor maintains effective control over the assets, accounting for them as secured debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481420/860-30-50-7

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