Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 29, 2020	Dec. 31, 2019	Jan. 01, 2019
Statement Of Financial Position [Abstract]
Preferred stock, shares authorized	5,000,000.0	5,000,000	5,000,000
Preferred stock, issued	0	0	0
Preferred stock, outstanding	0	0	0
Common stock, par value
Common stock, shares authorized		125,000,000	125,000,000
Common stock, shares issued		22,318,000	22,318,000
Common stock, shares outstanding		19,149,000	19,149,000
Accounts payable, related party trade payables	$ 0	$ 2,543

Amount for accounts payable to related parties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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