Goodwill and Identified Intangible Assets - Changes in Carrying Amount of Goodwill (Detail) $ in Thousands	3 Months Ended
	Mar. 27, 2020 USD ($)
Goodwill [Line Items]
Balance at beginning of period	$ 239,780
Foreign currency translation adjustment, net	(1,166)
Balance at end of period	238,614
Video [Member]
Goodwill [Line Items]
Balance at beginning of period	178,982
Foreign currency translation adjustment, net	(1,110)
Balance at end of period	177,872
Cable Access [Member]
Goodwill [Line Items]
Balance at beginning of period	60,798
Foreign currency translation adjustment, net	(56)
Balance at end of period	$ 60,742