Loans and Allowance for Loan Losses - Major classifications (Details) - USD ($)	3 Months Ended	12 Months Ended
Sep. 30, 2020	Jun. 30, 2020	Sep. 30, 2019	Jun. 30, 2019
Loans and Leases Receivable Disclosure [Line Items]
Total loans	$ 234,266,091	$ 238,653,905	$ 252,414,565
Less: allowance for loan losses	(1,353,484)	(1,353,427)	(1,286,674)	$ (1,293,965)
Total	232,912,607	237,300,478	251,127,891
Deferred loan origination fees	170,000	184,000
Construction, Land, Development
Loans and Leases Receivable Disclosure [Line Items]
Total loans	3,619,835	4,598,382	5,670,043
Less: allowance for loan losses	(10,859)	(13,795)	(5,670)	(4,319)
Total	3,608,976	4,584,587	5,664,373
1-4 Family Owner Occupied
Loans and Leases Receivable Disclosure [Line Items]
Total loans	92,578,159	100,506,311	114,503,607
Less: allowance for loan losses	(335,391)	(356,434)	(56,804)	(67,593)
Total	92,242,768	100,149,877	114,446,803
1-4 Family Non-Owner Occupied
Loans and Leases Receivable Disclosure [Line Items]
Total loans	20,831,506	21,213,680	20,493,732
Less: allowance for loan losses	(75,827)	(77,220)	(26,027)	(26,630)
Total	20,755,679	21,136,460	20,467,705
Multifamily
Loans and Leases Receivable Disclosure [Line Items]
Total loans	82,503,675	76,444,156	74,074,709
Less: allowance for loan losses	(350,641)	(286,665)	(111,112)	(109,870)
Total	82,153,034	76,157,491	73,963,597
Commercial Owner Occupied
Loans and Leases Receivable Disclosure [Line Items]
Total loans	6,588,790	6,733,183	8,362,568
Less: allowance for loan losses	(75,184)	(95,711)	(91,077)	(61,193)
Total	6,513,606	6,637,472	8,271,491
Commercial Non-Owner Occupied
Loans and Leases Receivable Disclosure [Line Items]
Total loans	20,620,785	20,237,534	19,604,096
Less: allowance for loan losses	(328,902)	(312,670)	(773,186)	(738,366)
Total	20,291,883	19,924,864	18,830,910
Consumer and Installment Loan
Loans and Leases Receivable Disclosure [Line Items]
Total loans	7,523,341	8,920,659	9,705,810
Less: allowance for loan losses	(89,941)	(97,312)	(72,508)	$ (70,058)
Total	$ 7,433,400	$ 8,823,347	$ 9,633,302

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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