Value Creation Plan (Disclosure of costs incurred under the Value Creation Plan) (Details) - Value Creation Plan [Member] - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 27, 2020	Jun. 29, 2019	Jun. 27, 2020	Jun. 29, 2019
Restructuring Reserve [Roll Forward]
Balance payable, Beginning			$ 4,227	$ 913
Costs incurred and charged to expense	$ 479	$ 1,675	2,474	3,533
Cash payments, net			(3,351)	(4,647)
Non-cash adjustments			816	2,102
Balance payable, Ending	4,166	1,901	4,166	1,901
Asset impairments and facility closure costs [Member]
Restructuring Reserve [Roll Forward]
Balance payable, Beginning			201	477
Costs incurred and charged to expense			365	308
Cash payments, net			(387)	(483)
Non-cash adjustments			(78)	0
Balance payable, Ending	101	302	101	302
Employee recruitment, retention and termination costs [Member]
Restructuring Reserve [Roll Forward]
Balance payable, Beginning			4,026	436
Costs incurred and charged to expense			1,320	2,947
Cash payments, net			(2,175)	(3,886)
Non-cash adjustments			894	2,102
Balance payable, Ending	4,065	1,599	4,065	1,599
Professional fees and temporary labor costs [Member]
Restructuring Reserve [Roll Forward]
Balance payable, Beginning			0	0
Costs incurred and charged to expense			789	278
Cash payments, net			(789)	(278)
Non-cash adjustments			0	0
Balance payable, Ending	$ 0	$ 0	$ 0	$ 0