Accumulated Other Comprehensive Loss - Reclassifications (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 27, 2020	Mar. 28, 2020	Jun. 29, 2019	Mar. 30, 2019	Jun. 27, 2020	Jun. 29, 2019
Reclassification from AOCL
Income tax expense	$ 15,956		$ 6,505		$ 22,498	$ 12,189
Net income	(44,911)	$ (28,092)	(18,251)	$ (16,791)	(73,003)	(35,042)
Defined Benefit Pension Plan Items | Amount Reclassified from AOCL
Reclassification from AOCL
Total before tax	296		215		696	430
Income tax expense	(77)		(52)		(181)	(105)
Net income	219		163		515	325
Amortization of unrecognized loss | Amount Reclassified from AOCL
Reclassification from AOCL
Total before tax	$ 296		$ 215		$ 696	$ 430