Schedule of Segment Reporting Information by Segment Charges (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 29, 2014	Jun. 30, 2013	Jun. 29, 2014	Jun. 30, 2013
Segment Reporting Information [Line Items]
Restructuring and other	$ 572	$ 259	$ 572	$ 591
Semiconductor Test
Segment Reporting Information [Line Items]
Cost of revenues-provision for excess and obsolete inventory	3,713	287	9,918	500
Total	3,713	287	9,918	500
System Test
Segment Reporting Information [Line Items]
Cost of revenues-provision for excess and obsolete inventory	440	290	1,181	1,209
Restructuring and other	146	131	146	375
Total	586	421	1,327	1,584
Wireless Test
Segment Reporting Information [Line Items]
Cost of revenues-provision for excess and obsolete inventory	879	1,398	3,972	4,066
Restructuring and other	426		426
Total	$ 1,305	$ 1,398	$ 4,398	$ 4,066