Stockholders' Equity - Basic and Diluted Net (Loss) Income Per Common Shares (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018
Numerator:
Net loss	$ (1,326)	$ (670)	$ 742	$ (840)	$ (1,172)	$ 345	$ (1,255)	$ (1,667)
Denominator:
Basic and diluted weighted average common shares outstanding (shares)	19,086,811			19,456,149			19,166,812	19,742,869
Basic and diluted net loss per common share (usd per share)	$ (0.07)			$ (0.04)			$ (0.07)	$ (0.09)