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Loans - Summary of loans (Details) - USD ($)	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2022
Loans and Leases Receivable Disclosure [Line Items]
Total loans	$ 185,292,000
Total loans		$ 199,935,846
Deferred loan fees	(47,000)
Deferred loan fees		(63,000)
Allowance for credit losses	(1,797,116)
Allowance for loan losses		(2,158,590)	$ (2,195,050)
Loans, net	183,448,000
Loans, net		197,713,756
Interest receivable	597,768	612,724
Consumer
Loans and Leases Receivable Disclosure [Line Items]
Allowance for loan losses		(2,000)
Provision for loans
Loans and Leases Receivable Disclosure [Line Items]
Interest receivable	513,782
Commercial real estate \| Commercial real estate
Loans and Leases Receivable Disclosure [Line Items]
Total loans	74,316,000
Total loans		84,580,946
Allowance for loan losses		(1,196,479)	(1,591,644)
Commercial \| Commercial and industrial
Loans and Leases Receivable Disclosure [Line Items]
Total loans	5,158,000
Total loans		6,878,209
Allowance for loan losses		(17,711)	(32,701)
Commercial \| Construction
Loans and Leases Receivable Disclosure [Line Items]
Total loans	1,313,000
Total loans		1,905,255
Allowance for loan losses		(6,302)	(55,029)
Residential \| One-to-four-family residential
Loans and Leases Receivable Disclosure [Line Items]
Total loans	57,808,000
Total loans		59,562,818
Allowance for loan losses		(206,771)	(263,951)
Residential \| Multi-family real estate
Loans and Leases Receivable Disclosure [Line Items]
Total loans	45,088,000
Total loans		44,183,871
Allowance for loan losses		(365,401)	(233,371)
Consumer Loans \| Consumer
Loans and Leases Receivable Disclosure [Line Items]
Total loans	$ 1,609,000
Total loans		2,824,747
Allowance for loan losses		$ (653)	$ (601)