Schedule of Geographic Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Apr. 02, 2021	Apr. 03, 2020
Segment Reporting Information [Line Items]
Revenue	$ 162,584	$ 155,468
United States
Segment Reporting Information [Line Items]
Revenue	59,230	59,205
Germany
Segment Reporting Information [Line Items]
Revenue	22,363	23,233
Rest of Europe
Segment Reporting Information [Line Items]
Revenue	35,575	33,085
China
Segment Reporting Information [Line Items]
Revenue	22,551	15,404
Rest of Asia-Pacific
Segment Reporting Information [Line Items]
Revenue	20,747	21,700
Other Countries
Segment Reporting Information [Line Items]
Revenue	$ 2,118	$ 2,841