Schedule of Segment Reporting Information by Segment Charges (Detail) - USD ($) $ in Thousands	3 Months Ended
	Apr. 03, 2016	Apr. 05, 2015
Segment Reporting Information [Line Items]
Restructuring and other	$ 1,587
Contingent consideration adjustment	1,173
Gain from the sale of an equity investment		$ (4,782)
Universal Robots
Segment Reporting Information [Line Items]
Contingent consideration adjustment	1,200
Semiconductor Test
Segment Reporting Information [Line Items]
Cost of revenues-inventory charge	3,685	531
Restructuring and other	414
Total	4,099	531
Wireless Test
Segment Reporting Information [Line Items]
Cost of revenues-inventory charge	605	846
Total	605	846
Corporate And Eliminations
Segment Reporting Information [Line Items]
Total	1,173	(4,782)
Corporate And Eliminations | Other (income) expense, net
Segment Reporting Information [Line Items]
Gain from the sale of an equity investment		$ (4,782)
Corporate And Eliminations | Universal Robots | Restructuring and other
Segment Reporting Information [Line Items]
Contingent consideration adjustment	$ 1,173