Loss Per Share - Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Earnings Per Share [Abstract]
Net loss	$ (2,859)	$ (115)	$ (8,654)	$ (19,140)
Less: Dividend paid in-kind to preferred stockholders	(85)	(82)	(250)	(182)
Less: Deemed dividend on preferred stock	(130)	(111)	(377)	(3,981)
Net loss attributable to common stockholders	(3,074)	(308)	(9,281)	(23,303)
Loss per share - basic:
Numerator for basic loss per share	$ (3,074)	$ (308)	$ (9,281)	$ (23,303)
Denominator for basic loss per share (shares)	9,234,869	2,945,035	7,107,678	2,942,202
Basic loss per common share (usd per share)	$ (0.33)	$ (0.10)	$ (1.31)	$ (7.92)
Loss per share - diluted:
Numerator for basic loss per share	$ (3,074)	$ (308)	$ (9,281)	$ (23,303)
Adjust: Warrant revaluation income for dilutive warrants	0	46	0	0
Net loss attributable to common stockholders - diluted	$ (3,074)	$ (354)	$ (9,281)	$ (23,303)
Denominator for basic loss per share (shares)	9,234,869	2,945,035	7,107,678	2,942,202
Incremental shares underlying dilutive in the money warrants outstanding (shares)	0	3,255	0	0
Denominator for diluted loss per share (shares)	9,234,869	2,948,290	7,107,678	2,942,202
Diluted net loss per common share (usd per share)	$ (0.33)	$ (0.12)	$ (1.31)	$ (7.92)