Balance Sheets (Parenthetical) - USD ($)	Jun. 30, 2018	Jun. 30, 2017
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 3,000	$ 3,000
Advance payments	$ 102,924	$ 1,366,504
Common stock, par value	$ 0.3333	$ 0.3333
Common stock, shares authorized	10,000,000	10,000,000
Common stock, shares issued	3,029,874	3,029,874
Common stock, shares outstanding	2,387,124	2,371,321
Unearned ESOP, shares	29,166	45,000
Treasury stock, shares	642,750	658,553

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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Number of common stock held in a trust that has been set up specifically to accumulate stock for the sole purpose of distribution to participating employees but not yet earned.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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