Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 26, 2020	Dec. 28, 2019
Statement Of Financial Position [Abstract]
Allowance for doubtful accounts and customer credits	$ 1,202	$ 957
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	50,000,000	50,000,000
Common stock, shares issued	32,304,686	32,558,168
Common stock, shares outstanding	32,304,686	32,558,168