Employee Retirement Plans Additional Information (Details) $ in Thousands	3 Months Ended
	Mar. 30, 2019 USD ($) plan	Mar. 31, 2018 USD ($)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net Periodic Benefit Cost, Other Components	$ 7,761	$ 9,705
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]
Defined Benefit Plan, Expected Return (Loss) on Plan Assets	$ (16,998)	(19,278)
Defined Benefit Plan, Service Cost	626	977
Defined Benefit Plan, Interest Cost	8,432	8,278
Defined Benefit Plan, Amortization of Gain (Loss)	157	1,032
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)	648	0
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement and Curtailment	0	287
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement	0	(24)
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)	$ (7,135)	$ (8,728)