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Restructuring and Other - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 27, 2020	Sep. 29, 2019	Sep. 27, 2020	Sep. 29, 2019
Restructuring Cost and Reserve
Contingent consideration adjustment			$ 13,116	$ 8,848
Semiconductor Test
Restructuring Cost and Reserve
Contingent consideration adjustment		$ 7,800		1,009
Severance benefit and charges	$ 500	500	1,200	2,300
Acquisition related costs	1,100		3,400
Impairment charges fixed assets		500		2,100
Contract termination settlement fee			4,000
Restructuring and other	0	0	4,000	0
Universal Robots (UR)
Restructuring Cost and Reserve
Contingent consideration adjustment		$ 3,800
Semiconductor Test, Industrial Automation and Corporate
Restructuring Cost and Reserve
Contingent consideration adjustment				$ 16,500
Restructuring and other			1,200
TER Corporate And Eliminations \| Universal Robots (UR)
Restructuring Cost and Reserve
Contingent consideration adjustment	$ 27,200		4,400
TER Corporate And Eliminations \| Mobile Industrial Robots (MiR)
Restructuring Cost and Reserve
Contingent consideration adjustment			$ 3,500