Loans - Activity in the allowance for loan losses by portfolio segment (Details) - USD ($)	12 Months Ended
Jun. 30, 2023	Jun. 30, 2024
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of year	$ 2,195,050
Charge-offs	(136,753)
Recoveries	100,293
Balance at end of year	2,158,590
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Collectively evaluated for impairment	2,158,590
Loans and Leases Receivable, Allowance	2,158,590
Loans - Individually evaluated for impairment	117,103	$ 0
Loans - Collectively evaluated for impairment	199,818,743
Loans and Leases Receivable, Gross	199,935,846
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Balance at end of year	2,000
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Loans and Leases Receivable, Allowance	2,000
Commercial real estate \| Commercial real estate
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of year	1,591,644
Charge-offs	(136,753)
Recoveries	98,084
Provision for Credit Losses	356,496
Balance at end of year	1,196,479
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Collectively evaluated for impairment	1,196,479
Loans and Leases Receivable, Allowance	1,196,479
Loans - Collectively evaluated for impairment	84,580,946
Loans and Leases Receivable, Gross	84,580,946
Commercial \| Commercial and industrial
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of year	32,701
Provision for Credit Losses	14,990
Balance at end of year	17,711
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Collectively evaluated for impairment	17,711
Loans and Leases Receivable, Allowance	17,711
Loans - Collectively evaluated for impairment	6,878,209
Loans and Leases Receivable, Gross	6,878,209
Commercial \| Construction
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of year	55,029
Provision for Credit Losses	48,727
Balance at end of year	6,302
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Collectively evaluated for impairment	6,302
Loans and Leases Receivable, Allowance	6,302
Loans - Collectively evaluated for impairment	1,905,255
Loans and Leases Receivable, Gross	1,905,255
Residential \| One-to-four-family residential
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of year	263,951
Provision for Credit Losses	57,180
Balance at end of year	206,771
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Collectively evaluated for impairment	206,771
Loans and Leases Receivable, Allowance	206,771
Loans - Individually evaluated for impairment	117,103
Loans - Collectively evaluated for impairment	59,445,715
Loans and Leases Receivable, Gross	59,562,818
Residential \| Multi-family real estate
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of year	233,371
Provision for Credit Losses	(132,030)
Balance at end of year	365,401
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Collectively evaluated for impairment	365,401
Loans and Leases Receivable, Allowance	365,401
Loans - Collectively evaluated for impairment	44,183,871
Loans and Leases Receivable, Gross	44,183,871
Consumer Loans \| Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of year	601
Recoveries	2,209
Provision for Credit Losses	2,157
Balance at end of year	653
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Collectively evaluated for impairment	653
Loans and Leases Receivable, Allowance	653
Loans - Collectively evaluated for impairment	2,824,747
Loans and Leases Receivable, Gross	2,824,747
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of year	17,753
Provision for Credit Losses	(347,520)
Balance at end of year	365,273
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Collectively evaluated for impairment	365,273
Loans and Leases Receivable, Allowance	$ 365,273

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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Amount of allowance for credit loss on financing receivable evaluated on collective basis. Excludes financing receivable evaluated on individual basis.

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Amount of financing receivable collectively evaluated for credit loss. Excludes financing receivable individually evaluated for credit loss.

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Amount of financing receivable individually evaluated for credit loss. Excludes financing receivable collectively evaluated for credit loss.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount of expense related to estimated loss from loan and lease transactions.

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