Loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Earnings Per Share [Abstract]
Net loss	$ (16,240)	$ (15,292)
Less: Dividend paid in-kind to preferred stockholders	(264)	0
Less: Deemed dividend on preferred stock	(4,099)	0
Earnings Per Share, Basic [Abstract]
Net loss	$ (20,603)	$ (15,292)
Denominator for basic loss per share (in shares)	15,454,199	14,641,528
Basic loss per common share (in dollars per share)	$ (1.33)	$ (1.04)
Earnings Per Share, Diluted [Abstract]
Numerator for basic loss per share	$ (20,603)	$ (15,292)
Warrant revaluation income (expense) for dilutive warrants	(34)	(1,958)
Numerator for diluted loss per share	$ (20,637)	$ (17,250)
Denominator for basic loss per share (in shares)	15,454,199	14,641,528
Incremental shares underlying in the money warrants outstanding (in shares)	5,919	6,006
Denominator for diluted loss per share (in shares)	15,460,118	14,647,534
Diluted net income (loss) per share (in dollars per share)	$ (1.33)	$ (1.18)