Segment Information - Summary Financial Infomation by reportable segments (Details) $ in Thousands		3 Months Ended
		Mar. 29, 2019 USD ($) segment	Mar. 30, 2018 USD ($)
Segment Reporting Information [Line Items]
Total Net Revenue	[1]	$ 80,106	$ 90,127
Gross Profit		41,849	47,183
Operating Income (Loss)		$ (8,408)	(9,327)
Number of Reportable Segments | segment		2
Operating Segments [Member]
Segment Reporting Information [Line Items]
Total Net Revenue		$ 80,106	90,127
Gross Profit		43,670	49,755
Operating Income (Loss)		(3,854)	371
Operating Segments [Member] | Video [Member]
Segment Reporting Information [Line Items]
Total Net Revenue		67,176	71,748
Gross Profit		38,602	41,226
Operating Income (Loss)		1,968	1,995
Operating Segments [Member] | Cable Access [Member]
Segment Reporting Information [Line Items]
Total Net Revenue		12,930	18,379
Gross Profit		5,068	8,529
Operating Income (Loss)		$ (5,822)	$ (1,624)

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