Schedule of Segment Reporting Information by Segment Charges (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 27, 2020	Sep. 29, 2019	Sep. 27, 2020	Sep. 29, 2019
Segment Reporting Information [Line Items]
Restructuring and other-employee severance	$ (27,701)	$ (6,500)	$ 1,915	$ (11,792)
Contingent consideration adjustment			13,116	8,848
Universal Robots (UR)
Segment Reporting Information [Line Items]
Contingent consideration adjustment		3,800
Semiconductor Test
Segment Reporting Information [Line Items]
Restructuring and other	0	0	4,000	0
Cost of revenues-inventory charge	1,131	1,867	7,956	5,319
Contingent consideration adjustment		7,800		1,009
Industrial Automation
Segment Reporting Information [Line Items]
Cost of revenues-inventory charge	0	0	664	604
Restructuring and other-employee severance	0	0	505	508
Contingent consideration adjustment			790	1,330
System Test
Segment Reporting Information [Line Items]
Cost of revenues-inventory charge	0	0	698	1,129
Wireless Test
Segment Reporting Information [Line Items]
Restructuring and other	1,802	724	3,957	1,892
Cost of revenues-inventory charge	0	0	0	566
Corporate And Eliminations
Segment Reporting Information [Line Items]
Contingent consideration adjustment	0	2,108	0	2,108
Corporate And Eliminations \| Universal Robots (UR) \| Restructuring and other
Segment Reporting Information [Line Items]
Contingent consideration adjustment	(1,086)	816	2,629	928
Corporate And Eliminations \| Mobile Industrial Robots (MiR) \| Restructuring and other
Segment Reporting Information [Line Items]
Selling and administrative – equity modification charge	0	$ (7,759)	(3,546)	$ (16,427)
Corporate And Eliminations \| AutoGuide [Member] \| Restructuring and other
Segment Reporting Information [Line Items]
Contingent consideration adjustment	$ (27,206)		$ (4,421)

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Selling and administrative equity modification charge.

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Amount of other expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses associated with a discontinued operation or an asset retirement obligation.

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