Schedule of Segment Reporting Information by Segment Charges (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 28, 2020	Jun. 30, 2019	Jun. 28, 2020	Jun. 30, 2019
Segment Reporting Information [Line Items]
Restructuring and other-employee severance	$ 37,222	$ (10,404)	$ 29,616	$ (5,292)
Contingent consideration adjustment			19,239	(8,701)
Universal Robots (UR)
Segment Reporting Information [Line Items]
Contingent consideration adjustment				3,800
Semiconductor Test
Segment Reporting Information [Line Items]
Restructuring and other			1,100
Cost of revenues-inventory charge	3,799	2,278	6,825	3,452
Restructuring and other-employee severance	0	0	0	924
Contingent consideration adjustment		(11,700)		(8,700)
Contract termination settlement charge	4,000	0	4,000	0
System Test
Segment Reporting Information [Line Items]
Cost of revenues-inventory charge	0	0	0	763
Industrial Automation
Segment Reporting Information [Line Items]
Restructuring and other	0	0	790	1,695
Wireless Test
Segment Reporting Information [Line Items]
Cost of revenues-inventory charge	1,582	829	2,155	1,168
Corporate And Eliminations \| Restructuring and other
Segment Reporting Information [Line Items]
Restructuring and other	750	0	750	0
Corporate And Eliminations \| Universal Robots (UR) \| Restructuring and other
Segment Reporting Information [Line Items]
Contingent consideration adjustment	2,974	0	3,715	0
Corporate And Eliminations \| Mobile Industrial Robots (MiR) \| Restructuring and other
Segment Reporting Information [Line Items]
Contingent consideration adjustment	(668)	(11,671)	(3,546)	(8,668)
Corporate And Eliminations \| AutoGuide [Member] \| Restructuring and other
Segment Reporting Information [Line Items]
Contingent consideration adjustment	$ 29,927	$ 0	$ 22,785	$ 0

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