Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Mar. 27, 2021	Dec. 26, 2020
Statement of Financial Position [Abstract]
Trade receivables, allowances	$ 272	$ 386
Common stock, par value	$ .001	$ 0.001
Common stock, shares authorized	75,000,000	75,000,000
Common stock, shares issued	27,588,389	27,560,686
Common stock, shares outstanding	27,588,389	27,560,686

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

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Face amount or stated value per share of common stock.

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