Restructuring Charges - Activity in Restructuring Reserve (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 28, 2020	Jun. 30, 2019	Jun. 28, 2020	Jun. 30, 2019
Restructuring Reserve [Roll Forward]
Balance at beginning of period			$ 0
Restructuring charges	$ 14,798	$ 0	14,798	$ 0
Cash payments			(4,689)
Non-cash restructuring charges			(3,145)
Foreign exchange rate changes			72
Balance at end of period	7,036		7,036
One-time Termination Benefits
Restructuring Reserve [Roll Forward]
Balance at beginning of period			0
Restructuring charges	10,386		10,386
Cash payments			(4,654)
Non-cash restructuring charges			0
Foreign exchange rate changes			60
Balance at end of period	5,792		5,792
Contract Termination Costs
Restructuring Reserve [Roll Forward]
Balance at beginning of period			0
Restructuring charges	3,995		3,995
Cash payments			(26)
Non-cash restructuring charges			(3,145)
Foreign exchange rate changes			5
Balance at end of period	829		829
Other Associated Costs
Restructuring Reserve [Roll Forward]
Balance at beginning of period			0
Restructuring charges	417		417
Cash payments			(9)
Non-cash restructuring charges			0
Foreign exchange rate changes			7
Balance at end of period	$ 415		$ 415