CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 01, 2021	Oct. 02, 2020	Oct. 01, 2021	Oct. 02, 2020
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 6,020	$ 3,892	$ 19,579	$ 2,586
Defined benefit plans:
Net change in plan assets	90	(334)	2,717	(387)
Reclassification into other income (expense), net	121	70	361	212
Foreign currency translation gain (loss)	29	316	(1,198)	402
Tax effect	(32)	(68)	37	(104)
Other comprehensive income (loss), net of tax	208	(16)	1,917	123
Comprehensive income	$ 6,228	$ 3,876	$ 21,496	$ 2,709