Other Comprehensive Income Changes in accumulated other comprehensive income (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 28, 2019	Sep. 29, 2018	Sep. 28, 2019	Sep. 29, 2018
Accumulated Other Comprehensive Income [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Net of Tax				$ (276,476)	$ (266,419)
Currency Translation Adjustment		$ (25,428)	$ (9,718)	(27,190)	(29,879)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax				(53,320)	(10,920)
Reclassification from accumulated other comprehensive income, current period, net of tax				1,953	229
Other Comprehensive Income (Loss), before Reclassifications, before Tax				(51,367)	(9,559)
Accumulated Other Comprehensive Income (Loss), Net of Tax		(327,843)	(275,978)	(327,843)	(275,978)
Accumulated Other Comprehensive (income) Loss, Defined Benefit Plan, Tax		(35,800)	(41,700)	(35,800)	(41,700)
Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Tax		(7,300)	6,800	(7,300)	6,800
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, Tax				1,000	1,900
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Tax				(9,900)	2,600
Accumulated Translation Adjustment [Member]
Accumulated Other Comprehensive Income [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Net of Tax				(112,771)	(69,721)
Currency Translation Adjustment				(27,190)	(29,879)
Reclassification from accumulated other comprehensive income, current period, net of tax				0	0
Other Comprehensive Income (Loss), before Reclassifications, before Tax				(27,190)	(29,879)
Accumulated Other Comprehensive Income (Loss), Net of Tax		(139,961)	(99,600)	(139,961)	(99,600)
Accumulated Defined Benefit Plans Adjustment
Accumulated Other Comprehensive Income/(Loss) [Line Items]
Other comprehensive income (loss), adopt of new accounting pronouncement				500
Accumulated Other Comprehensive Income [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Net of Tax				(170,938)	(203,063)
Other Comprehensive (Income) Loss, Defined Benefit Plan, before Reclassification Adjustment and Tax				4,966	8,660
Reclassification from accumulated other comprehensive income, current period, net of tax				0	0
Other Comprehensive Income (Loss), before Reclassifications, before Tax				4,966	8,173
Accumulated Other Comprehensive Income (Loss), Net of Tax		(165,972)	(194,890)	(165,972)	(194,890)
Interest Rate Swap | Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent
Accumulated Other Comprehensive Income [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Net of Tax				7,233	6,365
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax				(31,096)	10,299
Reclassification from accumulated other comprehensive income, current period, net of tax				1,953	229
Other Comprehensive Income (Loss), before Reclassifications, before Tax				(29,143)	12,147
Accumulated Other Comprehensive Income (Loss), Net of Tax		$ (21,910)	18,512	$ (21,910)	18,512
Accounting Standards Update 2018-02
Accumulated Other Comprehensive Income/(Loss) [Line Items]
Other comprehensive income (loss), adopt of new accounting pronouncement	[1]				1,132
Accumulated Other Comprehensive Income [Roll Forward]
Stranded Tax Effects Reclassified from OCI to Retained Earnings			$ 1,100		1,100
Accounting Standards Update 2018-02 | Accumulated Translation Adjustment [Member]
Accumulated Other Comprehensive Income/(Loss) [Line Items]
Other comprehensive income (loss), adopt of new accounting pronouncement	[1]				0
Accounting Standards Update 2018-02 | Accumulated Defined Benefit Plans Adjustment
Accumulated Other Comprehensive Income/(Loss) [Line Items]
Other comprehensive income (loss), adopt of new accounting pronouncement	[1]				(487)
Accounting Standards Update 2018-02 | Interest Rate Swap | Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent
Accumulated Other Comprehensive Income/(Loss) [Line Items]
Other comprehensive income (loss), adopt of new accounting pronouncement	[1]				$ 1,619

[1] As of December 31, 2017, the company adopted ASU 2018-02, "Income Statement-Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income". This guidance allowed for the reclassification of $1.1 million of stranded tax effects resulting from the Tax Cuts and Jobs Act of 2017 from accumulated other comprehensive income to retained earnings.