Summary of Significant Accounting Policies (Details 1) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Basic loss per share computation:
Net loss	$ (3,945)	$ (8,982)	$ (21,866)	$ (9,070)
Weighted average common shares - basic and diluted	53,625,768	53,391,948	53,532,277	53,297,889
Basic and diluted loss per share (in dollars per share)	$ (0.07)	$ (0.17)	$ (0.41)	$ (0.17)