Goodwill and Identified Intangible Assets - Changes in Carrying Amount of Goodwill (Detail) $ in Thousands	9 Months Ended
	Sep. 27, 2019 USD ($)
Goodwill [Line Items]
Balance at beginning of period	$ 240,618
Foreign currency translation adjustment, net	(1,884)
Balance at end of period	238,734
Video [Member]
Goodwill [Line Items]
Balance at beginning of period	179,839
Foreign currency translation adjustment, net	(1,869)
Balance at end of period	177,970
Cable Access [Member]
Goodwill [Line Items]
Balance at beginning of period	60,779
Foreign currency translation adjustment, net	(15)
Balance at end of period	$ 60,764