Loans - Summary of loans (Details) - USD ($)	Dec. 31, 2025	Jun. 30, 2025
Loans and Leases Receivable Disclosure [Line Items]
Accrued interest receivable	$ 706,026	$ 667,686
Total loans	213,732,000	202,571,000
Deferred loan fees	(116,000)	(67,000)
Allowance for loan losses	(1,702,526)	(1,708,269)
Loans, net	211,913,000	200,796,000
Provision for loans
Loans and Leases Receivable Disclosure [Line Items]
Accrued interest receivable	670,442	603,309
Commercial real estate \| Commercial real estate
Loans and Leases Receivable Disclosure [Line Items]
Total loans	90,819,000	91,867,000
Commercial \| Commercial and industrial
Loans and Leases Receivable Disclosure [Line Items]
Total loans	3,659,000	3,876,000
Commercial \| Construction
Loans and Leases Receivable Disclosure [Line Items]
Total loans	800,000	733,000
Commercial \| Consumer
Loans and Leases Receivable Disclosure [Line Items]
Total loans	2,767,000	1,957,000
Residential \| One-to-four-family residential
Loans and Leases Receivable Disclosure [Line Items]
Total loans	64,008,000	56,330,000
Residential \| Multi-family real estate
Loans and Leases Receivable Disclosure [Line Items]
Total loans	$ 51,679,000	$ 47,808,000

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

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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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
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-Publisher FASB
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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481598/310-20-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 946
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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