Loans and Allowance for Loan Losses - Major classifications (Details) - USD ($)	9 Months Ended	12 Months Ended
Mar. 31, 2020	Jun. 30, 2019	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018	Jun. 30, 2018
Loans and Leases Receivable Disclosure [Line Items]
Total loans	$ 246,549,421	$ 261,167,368		$ 262,525,803
Less: allowance for loan losses	(1,303,434)	(1,293,965)	$ (1,262,472)	(1,288,040)	$ (1,295,012)	$ (1,324,159)
Total	245,245,987	259,873,403		261,237,763
Deferred loan origination fees	245,000	312,000
Construction, Land, Development
Loans and Leases Receivable Disclosure [Line Items]
Total loans	4,762,278	4,318,845		3,316,605
Less: allowance for loan losses	(14,287)	(4,319)	(10,863)	(3,317)	(3,220)	(4,758)
Total	4,747,991	4,314,526		3,313,288
1-4 Family Owner Occupied
Loans and Leases Receivable Disclosure [Line Items]
Total loans	109,212,203	124,845,322		123,505,942
Less: allowance for loan losses	(399,104)	(67,593)	(99,975)	(66,593)	(25,850)	(7,300)
Total	108,813,099	124,777,729		123,439,349
1-4 Family Non-Owner Occupied
Loans and Leases Receivable Disclosure [Line Items]
Total loans	20,098,726	20,968,812		21,031,234
Less: allowance for loan losses	(73,159)	(26,630)	(22,168)	(26,499)	(28,534)	(71,053)
Total	20,025,567	20,942,182		21,004,735
Multifamily
Loans and Leases Receivable Disclosure [Line Items]
Total loans	78,150,768	73,246,392		74,684,437
Less: allowance for loan losses	(312,603)	(109,870)	(116,900)	(112,027)	(111,104)	(71,101)
Total	77,838,165	73,136,522		74,572,410
Commercial Owner Occupied
Loans and Leases Receivable Disclosure [Line Items]
Total loans	6,843,419	8,508,011		8,639,629
Less: allowance for loan losses	(94,144)	(61,193)	(80,090)	(62,655)	(134,288)	(131,906)
Total	6,749,275	8,446,818		8,576,974
Commercial Non-Owner Occupied
Loans and Leases Receivable Disclosure [Line Items]
Total loans	18,744,604	19,502,545		20,904,832
Less: allowance for loan losses	(267,111)	(738,366)	(809,722)	(754,873)	(881,797)	(925,355)
Total	18,477,493	18,764,179		20,149,959
Consumer and Installment Loan
Loans and Leases Receivable Disclosure [Line Items]
Total loans	8,737,423	9,777,441		10,443,124
Less: allowance for loan losses	(98,431)	(70,058)	$ (86,014)	(68,883)	$ (107,708)	$ (98,096)
Total	$ 8,638,992	$ 9,707,383		$ 10,374,241

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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