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Restructuring and Other - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended									12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Sep. 29, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jul. 01, 2018	Apr. 01, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Restructuring Cost and Reserve
Contingent consideration adjustment										$ (19,257)	$ 987	$ 7,820
Severance benefit and charges	$ 500		$ 7,800	$ 800	$ 800	$ 800		$ 3,900	$ 2,400
Acquisition related costs	200		800	500	1,300	500	$ 800	800	2,500
Wireless Test
Restructuring Cost and Reserve
Lease impairment												1,000
Semiconductor Test
Restructuring Cost and Reserve
Acquisition related costs										2,500	4,500
Semiconductor Test \| Property, Plant and Equipment
Restructuring Cost and Reserve
Impairment charges fixed assets												1,100
AutoGuide
Restructuring Cost and Reserve
Contingent consideration adjustment										3,000
Impairment of Fixed Assets and Expenses Related to the Japan Earthquake
Restructuring Cost and Reserve
Property insurance recovery												5,100
Impairment of Fixed Assets and Expenses Related to the Japan Earthquake \| Earthquake Related Expenses
Restructuring Cost and Reserve
Impairment charges fixed assets												800
Universal Robots (UR)
Restructuring Cost and Reserve
Contingent consideration adjustment				$ 11,700	$ 3,000	7,400		$ 5,000	$ 3,500	3,800	16,700
Severance benefit and charges		$ 1,700	$ 500				$ 800
Mobile Industrial Robots (MiR)
Restructuring Cost and Reserve
Contingent consideration adjustment	$ 5,800					$ 17,700					17,700
Semiconductor Test and Wireless Test \| Universal Robots (UR)
Restructuring Cost and Reserve
Contingent consideration adjustment												7,800
System Test and Semiconductor Test
Restructuring Cost and Reserve
Severance benefit and charges											$ 8,700
Semiconductor Test, Industrial Automation and Corporate
Restructuring Cost and Reserve
Severance benefit and charges										2,900		$ 3,800
Semiconductor Test, Industrial Automation and Corporate \| Mobile Industrial Robots (MiR)
Restructuring Cost and Reserve
Contingent consideration adjustment										$ 22,200