Summary of Restructuring Charges by Reportable Segment (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended			27 Months Ended	33 Months Ended
	Dec. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2020	Dec. 31, 2020
Restructuring Cost And Reserve [Line Items]
Restructuring costs		$ 4,477	$ 8,640	$ 2,025
2020 Restructuring
Restructuring Cost And Reserve [Line Items]
Restructuring costs		2,736
Cumulative Costs	$ 2,736
2020 Restructuring | Photonics
Restructuring Cost And Reserve [Line Items]
Restructuring costs		740
Cumulative Costs	740
2020 Restructuring | Vision
Restructuring Cost And Reserve [Line Items]
Restructuring costs		1,330
Cumulative Costs	1,330
2020 Restructuring | Precision Motion
Restructuring Cost And Reserve [Line Items]
Restructuring costs		524
Cumulative Costs	524
2020 Restructuring | Unallocated Corporate and Shared Services
Restructuring Cost And Reserve [Line Items]
Restructuring costs		142
Cumulative Costs	$ 142
2019 Restructuring
Restructuring Cost And Reserve [Line Items]
Restructuring costs		988	7,463	378
Cumulative Costs					$ 8,829
2019 Restructuring | Photonics
Restructuring Cost And Reserve [Line Items]
Restructuring costs		508	4,983
Cumulative Costs					5,491
2019 Restructuring | Vision
Restructuring Cost And Reserve [Line Items]
Restructuring costs		322	1,422	324
Cumulative Costs					2,068
2019 Restructuring | Precision Motion
Restructuring Cost And Reserve [Line Items]
Restructuring costs		139	590
Cumulative Costs					729
2019 Restructuring | Unallocated Corporate and Shared Services
Restructuring Cost And Reserve [Line Items]
Restructuring costs		19	468	54
Cumulative Costs					$ 541
2018 Restructuring
Restructuring Cost And Reserve [Line Items]
Restructuring costs		753	1,177	1,647
Cumulative Costs						$ 3,577
2018 Restructuring | Vision
Restructuring Cost And Reserve [Line Items]
Restructuring costs		$ 753	$ 1,177	1,579
Cumulative Costs						3,509
2018 Restructuring | Unallocated Corporate and Shared Services
Restructuring Cost And Reserve [Line Items]
Restructuring costs				$ 68
Cumulative Costs						$ 68