Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Oct. 03, 2020	Jul. 04, 2020	Apr. 04, 2020	Sep. 28, 2019	Jun. 29, 2019	Mar. 30, 2019	Oct. 03, 2020	Sep. 28, 2019
Cumulative balance of each component of other comprehensive income (loss) and income tax effects [Roll Forward]
Beginning Balance			$ (26,646)				$ (26,646)
Other comprehensive income before reclassifications							18,059
Tax effect							0
Other comprehensive income before reclassifications, net of tax							18,059
Amounts reclassified out of AOCI							6,835
Tax effect							(1,588)
Amounts reclassified out of AOCI, net of tax							5,247
Net other comprehensive income	$ 22,986	$ 21,848	(21,528)	$ (21,636)	$ 9,007	$ (8,532)	23,306	$ (21,161)
Ending Balance	(3,340)						(3,340)
Pension and Other Post-Retirement Actuarial Items [Member]
Cumulative balance of each component of other comprehensive income (loss) and income tax effects [Roll Forward]
Beginning Balance			(68,020)				(68,020)
Other comprehensive income before reclassifications							0
Tax effect							0
Other comprehensive income before reclassifications, net of tax							0
Amounts reclassified out of AOCI							6,835
Tax effect							(1,588)
Amounts reclassified out of AOCI, net of tax							5,247
Net other comprehensive income							5,247
Ending Balance	(62,773)						(62,773)
Currency Translation Adjustment [Member]
Cumulative balance of each component of other comprehensive income (loss) and income tax effects [Roll Forward]
Beginning Balance			41,374				41,374
Other comprehensive income before reclassifications							18,059
Tax effect							0
Other comprehensive income before reclassifications, net of tax							18,059
Amounts reclassified out of AOCI							0
Tax effect							0
Amounts reclassified out of AOCI, net of tax							0
Net other comprehensive income							18,059
Ending Balance	59,433						59,433
Accumulated Other Comprehensive Income (Loss) [Member]
Cumulative balance of each component of other comprehensive income (loss) and income tax effects [Roll Forward]
Beginning Balance			(26,646)				(26,646)
Net other comprehensive income	22,986	$ 21,848	$ (21,528)	$ (21,636)	$ 9,007	$ (8,532)
Ending Balance	$ (3,340)						$ (3,340)