Segment Information - Summary Financial Infomation by reportable segments (Details) $ in Thousands		3 Months Ended
		Mar. 27, 2020 USD ($) segment	Mar. 29, 2019 USD ($)
Segment Reporting Information [Line Items]
Total net revenue	[1]	$ 78,417	$ 80,106
Gross Profit		36,738	41,849
Operating income (loss)		$ (18,049)	(8,408)
Number of Reportable Segments | segment		2
Operating Segments [Member]
Segment Reporting Information [Line Items]
Total net revenue		$ 78,417	80,106
Gross Profit		38,321	43,670
Operating income (loss)		(9,532)	(3,854)
Operating Segments [Member] | Video [Member]
Segment Reporting Information [Line Items]
Total net revenue		54,372	67,176
Gross Profit		27,907	38,602
Operating income (loss)		(6,267)	1,968
Operating Segments [Member] | Cable Access [Member]
Segment Reporting Information [Line Items]
Total net revenue		24,045	12,930
Gross Profit		10,414	5,068
Operating income (loss)		$ (3,265)	$ (5,822)

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