Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 56	$ (40)
Other comprehensive loss:
Unrealized loss on investments, net of taxes	(19)
Other comprehensive loss	(19)
Comprehensive income (loss)	$ 37	$ (40)