Segment and Geographic Data, Operating Margin Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 29, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jul. 01, 2017	Apr. 01, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Operating margin reconciliation [Abstract]
Impairment of Intangible Assets	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ (1,559)
Restructuring and severance costs	0	0	0	0	(6,079)	(3,244)	(481)	(1,469)	0	(11,273)	(19,199)
U.S. pension settlement charges									0	0	(79,321)
Segment Operating Income									755,888	581,740	446,310
Consolidated Operating Income	$ 119,667	$ 138,098	$ 123,293	$ 104,062	76,006	95,416	85,005	67,578	485,120	324,005	197,058
Unallocated Other Income (Expense)					(8,981)	(9,228)	(9,296)	(17,136)	(68,344)	(44,641)	(102,842)
Income before taxes					$ 67,025	$ 86,188	$ 75,709	$ 50,442	416,776	279,364	94,216
Unallocated Amount to Segment [Member]
Operating margin reconciliation [Abstract]
Segment Operating Income									$ (270,768)	$ (246,462)	$ (228,494)