Fair Value of Financial Instruments - Estimated fair values of financial instruments (Details) - USD ($)	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2017
FINANCIAL ASSETS
Cash and cash equivalents	$ 5,630,770	$ 6,134,146	$ 5,618,063
Interest bearing deposits in banks	3,674,015	157,459
Available for sale securities	20,542,118	20,906,087
Loans, net	259,873,403	263,998,800
Loans held for sale	7,079,548	6,416,385
Federal Home Loan Bank stock	2,061,000	2,070,000
Accrued interest receivable	1,000,098	879,292
FINANCIAL LIABILITIES
Deposits	234,561,459	244,463,480
Federal Home Loan Bank advances	44,200,000	46,000,000
Accrued interest payable	5,882,086	5,180,996
Carrying Value
FINANCIAL ASSETS
Cash and cash equivalents	5,630,770	6,134,146
Interest bearing deposits in banks	3,674,015	157,459
Available for sale securities	20,542,118	20,906,087
Loans, net	259,873,403	263,998,800
Loans held for sale	7,079,548	6,416,385
Federal Home Loan Bank stock	2,061,000	2,070,000
Accrued interest receivable	1,000,098	879,292
FINANCIAL LIABILITIES
Deposits	234,561,459	244,463,480
Federal Home Loan Bank advances	44,200,000	46,000,000
Accrued interest payable	59,489	93,053
Fair Value
FINANCIAL ASSETS
Cash and cash equivalents	5,630,770	6,134,146
Interest bearing deposits in banks	3,674,015	157,459
Available for sale securities	20,542,118	20,906,087
Loans, net	256,666,403	256,952,400
Loans held for sale	7,079,548	6,416,385
Federal Home Loan Bank stock	2,061,000	2,070,000
Accrued interest receivable	1,000,098	879,292
FINANCIAL LIABILITIES
Deposits	217,705,000	220,870,600
Federal Home Loan Bank advances	44,200,000	46,000,000
Accrued interest payable	$ 59,489	$ 93,053

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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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Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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Amount of interest payable on debt, including, but not limited to, trade payables.

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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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