Segment Information - Summary Financial Infomation by reportable segments (Details) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 27, 2019 USD ($)	Sep. 28, 2018 USD ($)	Sep. 27, 2019 USD ($) segment	Sep. 28, 2018 USD ($)
Segment Reporting Information [Line Items]
Total Net Revenue	[1]	$ 115,725	$ 100,616	$ 280,696	$ 289,903
Gross Profit		75,540	50,102	161,317	148,888
Operating income (loss)		22,549	(3,651)	$ 6,377	(12,336)
Number of Reportable Segments | segment				2
Operating Segments [Member]
Segment Reporting Information [Line Items]
Total Net Revenue		115,725	100,616	$ 280,696	289,903
Gross Profit		77,571	52,018	166,748	155,234
Operating income (loss)		29,915	4,863	23,254	11,729
Operating Segments [Member] | Video [Member]
Segment Reporting Information [Line Items]
Total Net Revenue		60,055	73,344	198,856	224,300
Gross Profit		34,646	41,937	114,692	126,721
Operating income (loss)		(1,696)	5,258	4,731	13,492
Operating Segments [Member] | Cable Access [Member]
Segment Reporting Information [Line Items]
Total Net Revenue		55,670	27,272	81,840	65,603
Gross Profit		42,925	10,081	52,056	28,513
Operating income (loss)		$ 31,611	$ (395)	$ 18,523	$ (1,763)

[1] Revenue is attributed to countries based on the location of the customer.