Impairment and Restructuring Charges - Restructuring Accrual (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 28, 2019	Sep. 29, 2018	Sep. 28, 2019	Sep. 29, 2018
Restructuring Reserve
Beginning Accrual Balance			$ 8,640	$ 11,039
Additions Charged to Expense	$ 4,851	$ 3,589	11,719	8,360
Payments or Utilization			(13,076)	(13,144)
Ending Accrual Balance	7,283	6,255	7,283	6,255
Severance costs
Restructuring Reserve
Beginning Accrual Balance			5,353	7,232
Additions Charged to Expense			10,126	6,638
Payments or Utilization			(11,067)	(10,378)
Ending Accrual Balance	4,412	3,492	4,412	3,492
Other exit costs
Restructuring Reserve
Beginning Accrual Balance			3,287	3,807
Additions Charged to Expense			1,593	1,722
Payments or Utilization			(2,009)	(2,766)
Ending Accrual Balance	$ 2,871	$ 2,763	$ 2,871	$ 2,763