CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($)	Jun. 30, 2021	Jun. 30, 2020
CONSOLIDATED BALANCE SHEETS
Allowance for doubtful	$ 226,000	$ 326,000
Common stock, par (per share)	$ 0.01	$ 0.01
Common stock, authorized (in shares)	40,000,000	40,000,000
Common stock, issued (in shares)	21,244,799	21,241,066
Common stock, outstanding (in shares)	18,351,084	18,347,351
Treasury stock, shares	2,893,715	2,893,715

Amount of allowance for credit loss on accounts receivable.

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Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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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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