Segment Information, Geographic Information And Customer Concentration Segment Information - Summary Financial Information by Reportable Segments (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Revenue	[1]	$ 378,831	$ 402,874	$ 403,558
Gross profit		194,997	223,012	209,209
Operating Income (Loss)		(12,449)	13,083	(5,011)
Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue		378,831	402,874	403,558
Gross profit		198,753	230,704	217,199
Operating Income (Loss)		12,977	38,008	24,414
Operating Segments [Member] | Video [Member]
Segment Reporting Information [Line Items]
Revenue		242,510	278,028	313,828
Gross profit		132,092	162,156	178,170
Operating Income (Loss)		1,326	15,837	26,170
Operating Segments [Member] | Cable Access [Member]
Segment Reporting Information [Line Items]
Revenue		136,321	124,846	89,730
Gross profit		66,661	68,548	39,029
Operating Income (Loss)		$ 11,651	$ 22,171	$ (1,756)

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