Employee Retirement Plans Additional Information (Details) $ in Thousands	3 Months Ended
	Mar. 28, 2020 USD ($) plan	Mar. 30, 2019 USD ($)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net Periodic Benefit Cost, Other Components	$ 10,089	$ 7,761
Number of defined contribution 401K savings plans | plan	2
Non-US Plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	$ 645	626
Interest cost	6,418	8,432
Expected return on assets	(17,982)	(16,998)
Amortization of net (gain) loss	837	157
Amortization of prior service cost (credit)	638	648
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)	$ (9,444)	$ (7,135)