Loss Per Share - Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Earnings Per Share [Abstract]
Net loss	$ (2,901)	$ (5,007)
Less: Dividend paid in-kind to preferred stockholders	(82)	(20)
Less: Deemed dividend on preferred stock	(121)	(3,734)
Net loss attributable to common stockholders	(3,104)	(8,761)
Loss per share - basic:
Numerator for basic loss per share	$ (3,104)	$ (8,761)
Denominator for basic loss per share (shares)	28,356,351	14,694,613
Basic loss per common share (usd per share)	$ (0.11)	$ (0.60)
Loss per share - diluted:
Numerator for basic loss per share	$ (3,104)	$ (8,761)
Plus: Warrant revaluation income for dilutive warrants	0	7
Net loss attributable to common stockholders - diluted	$ (3,104)	$ (8,768)
Denominator for basic loss per share (shares)	28,356,351	14,694,613
Incremental shares underlying dilutive in the money warrants outstanding (shares)	0	2,597
Denominator for diluted loss per share (shares)	28,356,351	14,697,210
Diluted net loss per common share (usd per share)	$ (0.11)	$ (0.60)