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Loans - Summary of loans (Details) - USD ($)	Jun. 30, 2025	Jun. 30, 2024
Loans and Leases Receivable Disclosure [Line Items]
Interest receivable	$ 667,686	$ 597,768
Total loans	202,571,000	185,292,000
Deferred loan fees	(67,000)	(47,000)
Allowance for loan losses	(1,708,269)	(1,797,116)
Loans, net	200,796,000	183,448,000
Provision for loans
Loans and Leases Receivable Disclosure [Line Items]
Interest receivable	603,309	513,782
Commercial real estate | Commercial real estate
Loans and Leases Receivable Disclosure [Line Items]
Total loans	91,867,000	74,316,000
Commercial | Commercial and industrial
Loans and Leases Receivable Disclosure [Line Items]
Total loans	3,876,000	5,158,000
Commercial | Construction
Loans and Leases Receivable Disclosure [Line Items]
Total loans	733,000	1,313,000
Residential | One-to-four-family residential
Loans and Leases Receivable Disclosure [Line Items]
Total loans	56,330,000	57,808,000
Residential | Multi-family real estate
Loans and Leases Receivable Disclosure [Line Items]
Total loans	47,808,000	45,088,000
Consumer Loans | Consumer
Loans and Leases Receivable Disclosure [Line Items]
Total loans	$ 1,957,000	$ 1,609,000

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Amount excluding accrued interest, of allowance for credit loss on financing receivable, classified as current.

+ References

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-Topic 326
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-Section 45
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Amortized cost excluding accrued interest, before allowance for credit loss, fee, and loan in process, of financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
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Amount of unamortized loan commitment, origination, and other costs (fees) on financing receivable recognized as adjustment to yield. Excludes financing receivable covered under loss sharing agreement.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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