Fair Value of Financial Instruments - Estimated fair values of financial instruments (Details) - USD ($)	Jun. 30, 2020	Jun. 30, 2019
FINANCIAL ASSETS
Interest bearing deposits in banks	$ 2,713,164	$ 3,674,015
Available for sale securities	20,297,595	20,542,118
Loans, net	237,300,478	259,873,403
Loans held for sale	18,690,027	7,079,548
Federal Home Loan Bank stock	1,345,500	2,061,000
Accrued interest receivable	933,729	1,000,098
FINANCIAL LIABILITIES
Deposits	256,071,531	234,561,459
Federal Home Loan Bank borrowings	9,000,000	44,200,000
Accrued interest payable	14,008,786	5,882,086
Carrying Value
FINANCIAL ASSETS
Cash and cash equivalents	13,106,041	5,630,770
Interest bearing deposits in banks	2,713,164	3,674,015
Available for sale securities	20,297,595	20,542,118
Loans, net	237,300,478	259,873,403
Loans held for sale	18,690,027	7,079,548
Federal Home Loan Bank stock	1,345,500	2,061,000
Accrued interest receivable	933,729	1,000,098
FINANCIAL LIABILITIES
Deposits	256,071,531	234,561,459
Federal Home Loan Bank borrowings	9,000,000	44,200,000
Accrued interest payable	56,726	59,489
Fair Value
FINANCIAL ASSETS
Cash and cash equivalents	13,106,041	5,630,770
Interest bearing deposits in banks	2,713,164	3,674,015
Available for sale securities	20,297,595	20,542,118
Loans, net	247,100,558	256,666,403
Loans held for sale	18,690,027	7,079,548
Federal Home Loan Bank stock	1,345,500	2,061,000
Accrued interest receivable	933,729	1,000,098
FINANCIAL LIABILITIES
Deposits	251,928,460	217,705,000
Federal Home Loan Bank borrowings	9,000,000	44,200,000
Accrued interest payable	$ 56,726	$ 59,489

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

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Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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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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The face amount of loans that will be sold to other entities.

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