Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Jul. 01, 2018	Apr. 01, 2018	Jun. 30, 2019	Jul. 01, 2018
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance, beginning of period	$ 1,797,611	$ 1,773,949	$ 1,995,949	$ 1,844,277	$ 1,773,949	$ 1,844,277
Total other comprehensive income, net of tax	7,090	7,633	9,840	93,445	14,723	103,285
Balance, end of period	1,910,641	1,797,611	2,161,526	1,995,949	1,910,641	2,161,526
Accumulated Other Comprehensive Loss
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance, beginning of period	(622,051)	(629,684)	(406,604)	(500,049)	(629,684)	(500,049)
Other comprehensive income (loss) before reclassifications	2,361		5,312		4,144	102,695
Income tax benefit	2,108		(7,476)		1,519	(28,718)
Net other comprehensive (loss) income before reclassifications	4,469		(2,164)		5,663	73,977
Total reclassifications before tax	3,411		15,677		11,815	38,292
Income tax benefit (expense)	(790)		(3,673)		(2,755)	(8,984)
Net reclassifications	2,621		12,004		9,060	29,308
Total other comprehensive income, net of tax	7,090	7,633	9,840	93,445	14,723	103,285
Balance, end of period	(614,961)	(622,051)	(396,764)	(406,604)	(614,961)	(396,764)
Foreign currency translation adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance, beginning of period	(49,277)	(49,608)	(14,937)	(21,852)	(49,608)	(21,852)
Other comprehensive income (loss) before reclassifications	11,152		(26,482)		11,758	(19,567)
Income tax benefit	118		0		(157)	0
Net other comprehensive (loss) income before reclassifications	11,270		(26,482)		11,601	(19,567)
Total reclassifications before tax	0		0		0	0
Income tax benefit (expense)	0		0		0	0
Net reclassifications	0		0		0	0
Total other comprehensive income, net of tax	11,270		(26,482)		11,601	(19,567)
Balance, end of period	(38,007)	(49,277)	(41,419)	(14,937)	(38,007)	(41,419)
Derivative financial instruments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance, beginning of period	1,344	1,785	(16,489)	(17,254)	1,785	(17,254)
Other comprehensive income (loss) before reclassifications	(8,791)		31,794		(7,614)	25,888
Income tax benefit	1,990		(7,476)		1,676	(6,089)
Net other comprehensive (loss) income before reclassifications	(6,801)		24,318		(5,938)	19,799
Total reclassifications before tax	(6,708)		(530)		(8,423)	6,378
Income tax benefit (expense)	1,586		132		1,997	(1,492)
Net reclassifications	(5,122)		(398)		(6,426)	4,886
Total other comprehensive income, net of tax	(11,923)		23,920		(12,364)	24,685
Balance, end of period	(10,579)	1,344	7,431	(16,489)	(10,579)	7,431
Pension and postretirement benefit plans
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance, beginning of period	(574,118)	(581,861)	(375,178)	(460,943)	(581,861)	(460,943)
Other comprehensive income (loss) before reclassifications	0		0		0	96,374
Income tax benefit	0		0		0	(22,629)
Net other comprehensive (loss) income before reclassifications	0		0		0	73,745
Total reclassifications before tax	10,119		16,207		20,238	31,914
Income tax benefit (expense)	(2,376)		(3,805)		(4,752)	(7,492)
Net reclassifications	7,743		12,402		15,486	24,422
Total other comprehensive income, net of tax	7,743		12,402		15,486	98,167
Balance, end of period	(566,375)	$ (574,118)	(362,776)	$ (375,178)	(566,375)	(362,776)
Pension and postretirement benefit plans - Prior service credits
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total reclassifications before tax	(1,078)		(565)		(2,156)	(1,131)
Pension and postretirement benefit plans - Actuarial losses
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total reclassifications before tax	$ 11,197		$ 16,772		$ 22,394	$ 33,045