CONDENSED CONSOLIDATED BALANCE SHEETS (Parentheticals) - USD ($) $ in Thousands	Mar. 28, 2020	Dec. 28, 2019
Statement of Financial Position [Abstract]
Allowance for doubtful accounts receivable	$ 3,875	$ 3,236
Debt discount, current	74	74
Debt discount, noncurrent	$ 11,861	$ 12,481
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)	9,366,641	9,365,768
Common stock, shares outstanding (in shares)	9,366,641	9,365,768

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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