Loans and Allowance for Loan Losses - Major classifications (Details) - USD ($)	3 Months Ended	12 Months Ended
Sep. 30, 2021	Jun. 30, 2021	Sep. 30, 2020	Jun. 30, 2020
Loans and Leases Receivable Disclosure [Line Items]
Total loans	$ 227,074,298	$ 216,832,440	$ 234,266,091
Less: allowance for loan losses	(1,462,889)	(1,412,489)	(1,353,484)	$ (1,353,427)
Total	225,611,409	215,419,951	232,912,607
Deferred loan origination fees	133,000	99,000
Construction, Land, Development
Loans and Leases Receivable Disclosure [Line Items]
Total loans	8,070,394	2,458,461	3,619,835
Less: allowance for loan losses	(36,317)	(11,063)	(10,859)	(13,795)
Total	8,034,077	2,447,398	3,608,976
Residential \| 1-4 Family Owner Occupied
Loans and Leases Receivable Disclosure [Line Items]
Total loans	74,012,356	72,011,570	92,578,159
Less: allowance for loan losses	(339,916)	(326,408)	(335,391)	(356,434)
Total	73,672,440	71,685,162	92,242,768
Residential \| 1-4 Family Non-Owner Occupied
Loans and Leases Receivable Disclosure [Line Items]
Total loans	21,211,782	22,368,557	20,831,506
Less: allowance for loan losses	(100,119)	(115,645)	(75,827)	(77,220)
Total	21,111,663	22,252,912	20,755,679
Residential \| Multifamily
Loans and Leases Receivable Disclosure [Line Items]
Total loans	96,821,185	91,876,323	82,503,675
Less: allowance for loan losses	(484,106)	(459,382)	(350,641)	(286,665)
Total	96,337,079	91,416,941	82,153,034
Commercial \| Commercial Owner Occupied
Loans and Leases Receivable Disclosure [Line Items]
Total loans	6,296,756	6,405,226	6,588,790
Less: allowance for loan losses	(101,647)	(99,851)	(75,184)	(95,711)
Total	6,195,109	6,305,375	6,513,606
Commercial \| Commercial Non-Owner Occupied
Loans and Leases Receivable Disclosure [Line Items]
Total loans	13,458,274	14,182,106	20,620,785
Less: allowance for loan losses	(218,697)	(230,459)	(328,902)	(312,670)
Total	13,239,577	13,951,647	20,291,883
Consumer
Loans and Leases Receivable Disclosure [Line Items]
Total loans	7,203,551	7,530,197	7,523,341
Less: allowance for loan losses	(61,871)	(66,523)	(89,941)	$ (97,312)
Total	$ 7,141,680	$ 7,463,674	$ 7,433,400

The net increase(decrease) in interest income during the period representing the allocation of deferred loan origination fees less deferred loan origination costs using the effective interest method over the term of the debt arrangement to which they pertain taking into account the effect of prepayments.

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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 after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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