Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Jun. 29, 2019	Dec. 29, 2018
Statement of Financial Position [Abstract]
Trade receivables, allowances	$ 202	$ 202
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	75,000,000	75,000,000
Common stock, shares issued	27,404,469	27,487,594
Common stock, shares outstanding	27,404,469	27,487,594

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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