Quarterly Financial Information (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended								12 Months Ended
		Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
QUARTERLY FINANCIAL INFORMATION (UNAUDITED) [Abstract]
Revenues		$ 18,063	$ 16,683	$ 15,854	$ 14,120	$ 13,176	$ 11,828	$ 16,409	$ 11,920	$ 64,720	$ 53,333
Gross margin		7,692	7,436	7,264	6,219	6,037	5,592	7,733	5,398	28,611	24,760
Income (loss) from operations		1,473	1,329	875	(318)	55	(163)	1,662	(539)	3,359	1,015
Net income (loss)		$ 1,193	$ 1,067	$ 740	$ (173)	$ 503	$ (72)	$ 1,095	$ (214)	$ 2,827	$ 1,312
Net income (loss) per share - Basic (in usd per share)	[1]	$ 0.17	$ 0.15	$ 0.11	$ (0.02)	$ 0.07	$ (0.01)	$ 0.16	$ (0.03)	$ 0.40	$ 0.19
Net income (loss) per share - Diluted (in usd per share)	[1]	$ 0.16	$ 0.15	$ 0.10	$ (0.02)	$ 0.07	$ (0.01)	$ 0.15	$ (0.03)	$ 0.39	$ 0.19

[1] The summation of quarterly per share amounts may not equal the calculation for the full year, as each quarterly calculation is performed discretely.