Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 30, 2019	Dec. 29, 2018
Statement Of Financial Position [Abstract]
Allowance for doubtful accounts, accounts receivable	$ 1,482	$ 1,336
Preferred stock, shares authorized	2,000,000	2,000,000
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares outstanding	0	0
Common stock, shares authorized	50,000,000	50,000,000
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares issued	31,995,700	31,964,775
Common stock, shares outstanding	31,995,700	31,964,775