Goodwill and Identified Intangible Assets - Changes in Carrying Amount of Goodwill (Detail) $ in Thousands	6 Months Ended
	Jun. 28, 2019 USD ($)
Goodwill [Line Items]
Balance at beginning of period	$ 240,618
Foreign currency translation adjustment	(283)
Balance at end of period	240,335
Video [Member]
Goodwill [Line Items]
Balance at beginning of period	179,839
Foreign currency translation adjustment	(282)
Balance at end of period	179,557
Cable Access [Member]
Goodwill [Line Items]
Balance at beginning of period	60,779
Foreign currency translation adjustment	(1)
Balance at end of period	$ 60,778