Revenue Recognition (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenue Recognition and Deferred Revenue [Abstract]
Digital video headend products	$ 801	$ 1,292	$ 2,603	$ 5,482
CPE	1,379	1,498	3,051	2,691
DOCSIS data products	235	884	1,807	1,989
HFC distribution products	599	645	1,769	1,872
Analog video headend products	323	366	838	1,249
NXG	89	91	570	535
Contract manufactured products	28	319	101	393
Transcoders	543		937	33
Other	174	183	376	553
Total	$ 4,171	$ 5,278	$ 12,052	$ 14,797