Domestic and Foreign Revenues - Significant Foreign Revenues from Operations (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Entity Wide Revenue Major Customer [Line Items]
Revenues from operations	$ 8,588	$ 6,338	$ 23,058	$ 18,440
Malaysia [Member]
Entity Wide Revenue Major Customer [Line Items]
Revenues from operations	1,109	771	2,788	2,238
Hong Kong [Member]
Entity Wide Revenue Major Customer [Line Items]
Revenues from operations	234	218	668	451
All other foreign countries [Member]
Entity Wide Revenue Major Customer [Line Items]
Revenues from operations	873	519	2,274	1,800
Foreign [Member]
Entity Wide Revenue Major Customer [Line Items]
Revenues from operations	2,216	1,508	5,730	4,489
Domestic [Member]
Entity Wide Revenue Major Customer [Line Items]
Revenues from operations	$ 6,372	$ 4,830	$ 17,328	$ 13,951