Revenue Recognition (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Disaggregated revenues	$ 5,277	$ 6,164	$ 10,640	$ 12,137
Digital video headend products [Member]
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Disaggregated revenues	2,542		5,085
Data products [Member]
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Disaggregated revenues	1,055		2,454
HFC distribution products [Member]
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Disaggregated revenues	761		1,502
Analog video headend products [Member]
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Disaggregated revenues	493		823
Contract manufactured products [Member]
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Disaggregated revenues	155		379
Other [Member]
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Disaggregated revenues	$ 271		$ 397