Segment Information - Information About Segments (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 28, 2014	Sep. 29, 2013	Sep. 28, 2014	Sep. 29, 2013
Segment Reporting Information [Line Items]
Product revenue	$ 158,631	$ 83,464	$ 345,142	$ 237,834
Service revenue	10,725	7,324	23,945	20,356
Operating income	59,428	23,379	112,593	61,533
Operating Segments | MVSD
Segment Reporting Information [Line Items]
Product revenue	148,970	75,184	316,657	215,515
Service revenue	5,386	2,758	11,291	7,151
Operating income	62,250	26,038	124,726	71,641
Operating Segments | SISD
Segment Reporting Information [Line Items]
Product revenue	9,661	8,280	28,485	22,319
Service revenue	5,339	4,566	12,654	13,205
Operating income	3,925	2,916	9,509	6,875
Reconciling Items
Segment Reporting Information [Line Items]
Operating income	$ (6,747)	$ (5,575)	$ (21,642)	$ (16,983)