Summary of Restructuring Charges by Reportable Segment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 01, 2021	Oct. 02, 2020	Oct. 01, 2021	Oct. 02, 2020
Restructuring Cost And Reserve [Line Items]
Restructuring costs	$ 5,185	$ 1,074	$ 7,896	$ 2,427
2020 Restructuring
Restructuring Cost And Reserve [Line Items]
Restructuring costs	5,185	1,006	7,688	1,006
2020 Restructuring | Photonics
Restructuring Cost And Reserve [Line Items]
Restructuring costs	2,349		2,839
2020 Restructuring | Vision
Restructuring Cost And Reserve [Line Items]
Restructuring costs	193	$ 1,006	890	$ 1,006
2020 Restructuring | Precision Motion
Restructuring Cost And Reserve [Line Items]
Restructuring costs	$ 2,643		$ 3,959