Loans and Allowance for Credit Losses - Additional Information (Detail)	12 Months Ended
Jun. 30, 2025 USD ($) SecurityLoan	Jun. 30, 2024 USD ($) SecurityLoan
Loans and Allowance for Credit Losses [Line Items]
Maximum term of fixed-rate one- to four-family residential mortgage loans	15 years
Number of default loans \| SecurityLoan	0	0
Foreclosed residential real estate properties	$ 165,000	$ 0
Fair Value, Concentration of Risk, Collateral Policy [Member]
Loans and Allowance for Credit Losses [Line Items]
Commercial and multi-family real estate	$ 339,861,000	346,499,000
Troubled Debt Restructurings [Member]
Loans and Allowance for Credit Losses [Line Items]
Minimum period for default	90 days
Residential Real Estate [Member]
Loans and Allowance for Credit Losses [Line Items]
Foreclosed residential real estate properties	$ 165,000	0
One- to four-family [Member]
Loans and Allowance for Credit Losses [Line Items]
Loans held for sale	$ 0	0
Maximum term of fixed-rate one- to four-family residential mortgage loans	15 years
Purchased Loans and Loan Participations [Member]
Loans and Allowance for Credit Losses [Line Items]
Approximate amount of purchase loans included in loans receivable	$ 198,000	253,000
Approximate amount of loans included on out-of-area participation	55,849,000	51,798,000
Amount within 100 miles of primary area	$ 38,860,000	$ 34,929,000

Financing receivable modifications number of contracts.

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- Definition

Loans and Allowance for Credit Losses [Line Items]

+ References

No definition available.

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- Definition

Loans and leases receivable commercial loan participations.

+ References

No definition available.

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- Definition

Loans and leases receivable loans commercial loan participations outside primary market area.

+ References

No definition available.

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- Definition

Loans and leases receivable purchased loans.

+ References

No definition available.

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- Definition

Minimum period for default.

+ References

No definition available.

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- Definition

Term period on residential mortgage loan.

+ References

No definition available.

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- Definition

Fair value of loan receivable subject to concentration of credit or market risk or both.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-21

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- Definition

Amount, after valuation allowance, of financing receivable held for sale and not part of disposal group. Excludes loan covered under loss sharing agreement and loan classified as investment in debt security.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481990/310-10-45-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 948
-SubTopic 310
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477011/948-310-45-1

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- Definition

Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 20
-Name Accounting Standards Codification
-Section 40
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481628/310-20-40-7

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481990/310-10-45-3

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-11

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