Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Jul. 02, 2021	Dec. 31, 2020
Statement Of Financial Position [Abstract]
Accounts receivable, allowances	$ 348	$ 561
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	150,000,000	150,000,000
Common stock, shares issued	27,017,824	27,017,824
Treasury stock, shares	11,689,792	11,841,960