Summary of Restructuring Costs for Each Segment and Unallocated Corporate and Shared Services (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2016	Sep. 29, 2017	Sep. 30, 2016
Restructuring Cost And Reserve [Line Items]
Restructuring Costs	$ (1,621)	$ 200	$ 3,063
2016 Restructuring
Restructuring Cost And Reserve [Line Items]
Restructuring Costs	(1,621)	186	2,955
2016 Restructuring | Photonics
Restructuring Cost And Reserve [Line Items]
Restructuring Costs	45		813
2016 Restructuring | Vision
Restructuring Cost And Reserve [Line Items]
Restructuring Costs	(1,728)	185	1,730
2016 Restructuring | Precision Motion
Restructuring Cost And Reserve [Line Items]
Restructuring Costs			106
2016 Restructuring | Unallocated Corporate and Shared Services
Restructuring Cost And Reserve [Line Items]
Restructuring Costs	$ 62	$ 1	$ 306