Schedule of Segment Reporting Information by Segment Charges (Detail) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jul. 03, 2016	Jul. 05, 2015	Jul. 03, 2016	Jul. 05, 2015
Segment Reporting Information [Line Items]
Goodwill impairment		$ 254,946		$ 254,946
Acquired intangible assets impairment		83,339		83,339
Restructuring and other		2,608	$ (385)	4,195	$ (385)
Property insurance recovery and proceeds		(5,051)		(5,051)
Contingent consideration adjustment		1,300		2,478	(1,600)
Gain from the sale of an equity investment					(5,406)
Universal Robots
Segment Reporting Information [Line Items]
Contingent consideration adjustment		800		1,900
Acquisition related costs					1,000
Avionics Interface Technologies, LLC
Segment Reporting Information [Line Items]
Contingent consideration adjustment		600		600
ZTEC Instruments, Inc.
Segment Reporting Information [Line Items]
Contingent consideration adjustment			(1,600)		(1,600)
Semiconductor Test
Segment Reporting Information [Line Items]
Cost of revenues-inventory charge		2,234	6,409	5,919	6,940
Restructuring and other		337	305	751	305
Total		2,571	6,714	6,670	7,245
Corporate And Eliminations
Segment Reporting Information [Line Items]
Total		1,305	(1,264)	2,478	(6,046)
Corporate And Eliminations | Restructuring and other
Segment Reporting Information [Line Items]
Property insurance recovery and proceeds		(5,051)		(5,051)
Corporate And Eliminations | Other (income) expense, net
Segment Reporting Information [Line Items]
Gain from the sale of an equity investment			(624)		(5,406)
Corporate And Eliminations | Impairment of fixed assets and expenses related to the Japan earthquake | Restructuring and other
Segment Reporting Information [Line Items]
Building impairment and other expenses		5,051		5,051
Corporate And Eliminations | Universal Robots | Restructuring and other
Segment Reporting Information [Line Items]
Contingent consideration adjustment		755		1,928
Acquisition related costs			960		960
Corporate And Eliminations | Avionics Interface Technologies, LLC | Restructuring and other
Segment Reporting Information [Line Items]
Contingent consideration adjustment		550		550
Corporate And Eliminations | ZTEC Instruments, Inc. | Restructuring and other
Segment Reporting Information [Line Items]
Contingent consideration adjustment			(1,600)		(1,600)
Industrial Automation
Segment Reporting Information [Line Items]
Cost of revenues-inventory step-up	[1]		595		595
Wireless Test
Segment Reporting Information [Line Items]
Goodwill impairment		254,946		254,946
Acquired intangible assets impairment		83,339		83,339
Cost of revenues-inventory charge		5,271	330	5,876	1,176
Restructuring and other		967		967
Total		344,523	330	345,128	1,176
System Test
Segment Reporting Information [Line Items]
Cost of revenues-inventory charge		$ 237	$ 7,702	$ 320	$ 7,765

[1] Included in the cost of revenues for the three and six months ended July 5, 2015 is the cost for purchase accounting inventory step-up.