Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Jun. 28, 2020	Jun. 30, 2019
Statement Of Financial Position [Abstract]
Allowance for doubtful accounts receivable	$ 500	$ 500
Common stock, shares authorized	12,000,000	12,000,000
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares issued	7,358,812	7,304,994
Treasury stock, shares	3,609,193	3,613,439

Amount of allowance for credit loss on accounts receivable, classified as current.

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-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Face amount or stated value per share of common stock.

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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 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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