Accumulated Other Comprehensive Loss - Before and After Tax Amounts for Comprehensive Income (Loss) Components (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 29, 2020	Mar. 31, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income/(loss)	$ (93,987)	$ 6,048
Foreign Currency Items
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income/(loss) before tax	(85,994)	(2,852)
Other comprehensive income/(loss), tax	(7,581)	0
Other comprehensive income/(loss)	(93,575)	(2,852)
Defined benefit pension items
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income/(loss) before reclassifications before tax	264	(681)
Other comprehensive income/(loss) before reclassifications, tax	(67)	173
Other comprehensive income/(loss) before reclassifications, net of tax	197	(508)
Other comprehensive income/(loss) before tax	7,748	9,573
Other comprehensive income/(loss), tax	(1,968)	(2,417)
Other comprehensive income/(loss)	5,780	7,156
Defined benefit pension items | Net Income
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amounts reclassified from accumulated other comprehensive income/(loss) before tax	7,484	10,254
Amounts reclassified from accumulated other comprehensive income/(loss), tax	(1,901)	(2,590)
Amounts reclassified from accumulated other comprehensive income/(loss) net of tax	5,583	7,664
Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income/(loss) before reclassifications before tax	(7,333)	3,022
Other comprehensive income/(loss) before reclassifications, tax	1,713	(766)
Other comprehensive income/(loss) before reclassifications, net of tax	(5,620)	2,256
Other comprehensive income/(loss) before tax	(5,943)	2,513
Other comprehensive income/(loss), tax	1,388	(649)
Other comprehensive income/(loss)	(4,555)	1,864
Cash Flow Hedges | Fixed Assets
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amounts reclassified from accumulated other comprehensive income/(loss) before tax	0	(45)
Amounts reclassified from accumulated other comprehensive income/(loss), tax	0	0
Amounts reclassified from accumulated other comprehensive income/(loss) net of tax	0	(45)
Cash Flow Hedges | Net Income
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amounts reclassified from accumulated other comprehensive income/(loss) before tax	1,390	(464)
Amounts reclassified from accumulated other comprehensive income/(loss), tax	(325)	117
Amounts reclassified from accumulated other comprehensive income/(loss) net of tax	1,065	(347)
Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income/(loss) before tax	(84,189)	9,234
Other comprehensive income/(loss), tax	(8,161)	(3,066)
Other comprehensive income/(loss)	$ (92,350)	$ 6,168