Segment Information - Information About Segments (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]
Product revenue	$ 102,942	$ 79,698	$ 186,511	$ 154,370
Service revenue	5,860	6,812	13,220	13,032
Operating income	30,722	20,173	53,165	38,154
Operating Segments | MVSD
Segment Reporting Information [Line Items]
Product revenue	90,069	72,012	167,687	140,331
Service revenue	2,207	2,301	5,905	4,393
Operating income	34,184	23,527	62,476	45,603
Operating Segments | SISD
Segment Reporting Information [Line Items]
Product revenue	12,873	7,686	18,824	14,039
Service revenue	3,653	4,511	7,315	8,639
Operating income	4,571	2,227	5,584	3,959
Reconciling Items
Segment Reporting Information [Line Items]
Operating income	$ (8,033)	$ (5,581)	$ (14,895)	$ (11,408)