CONDENSED CONSOLIDATED BALANCE SHEETS (Parentheticals) - USD ($) $ in Thousands	Sep. 28, 2019	Dec. 29, 2018
Statement of Financial Position [Abstract]
Allowance for doubtful accounts receivable	$ 3,811	$ 3,656
Debt discount, current	74	64
Debt discount, noncurrent	$ 12,081	$ 12,665
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	20,000,000	20,000,000
Common stock, shares issued (in shares)	9,364,959	9,293,794
Common stock, shares outstanding (in shares)	9,364,959	9,293,794

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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Amount, after accumulated amortization, of debt discount.

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