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	Dec. 31, 2023	Jun. 30, 2023
Financial assets
Cash and cash equivalents	$ 8,169	$ 10,988
Interest-bearing time deposits in banks	750	1,250
Loans, net of allowance for loan losses	653,549	587,457
Federal Home Loan Bank stock	5,419	3,127
Accrued interest receivable	3,758	2,781
Financial liabilities
Deposits	678,045	735,314
Repurchase agreements	16,040	10,787
Federal Home Loan Bank advances	98,050	19,500
Other borrowings	34,375	0
Advances from borrowers for taxes and insurance	1,235	1,233
Accrued interest payable	2,849	1,666
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	8,169	10,988
Interest-bearing time deposits in banks	750	1,250
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	5,419	3,127
Accrued interest receivable	3,758	2,781
Financial liabilities
Deposits	359,980	451,718
Repurchase agreements	16,040	10,787
Federal Home Loan Bank advances	98,145	19,382
Other borrowings	34,450
Advances from borrowers for taxes and insurance	1,235	1,233
Accrued interest payable	2,849	1,666
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 loan losses	629,305	564,432
Financial liabilities
Deposits	317,804	282,351
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.

+ Details

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.15(5))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

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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//1943274/2147480876/942-470-45-1

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- Definition

Amount 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. Excludes cash and cash equivalents within disposal group and discontinued operation.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(1))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

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-Section 45
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-URI https://asc.fasb.org//1943274/2147483467/210-10-45-1

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-Section 45
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-4

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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

No definition available.

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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://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(25))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.12)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

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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://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 325
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481026/942-325-45-1

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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
-Section 45
-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://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(15)(a))
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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 946
-SubTopic 310
-Name Accounting Standards Codification
-Section 45
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-Subparagraph (a)
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
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-Subparagraph (SX 210.5-02(3)(a)(4))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

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- Definition

The carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.13,16)
-Publisher FASB
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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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