Equity - Preferred Stock (Details) - USD ($) $ / shares in Units, $ in Thousands			12 Months Ended
	Mar. 08, 2017	Mar. 07, 2017	Dec. 31, 2017	Dec. 31, 2016	Mar. 31, 2017
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)			5,000,000
Preferred stock, par value (in dollars per share)			$ 0.001	$ 0.001
Deemed dividend on preferred stock			$ 4,099	$ 0
Dividend paid in-kind to preferred stockholders			$ 264	$ 0
2017 Private Placement
Class of Stock [Line Items]
Preferred shares issued (in shares)		1
Preferred stock, par value (in dollars per share)		$ 1,000
Conversion price (usd per share)		$ 2.3271
Number of common shares authorized for purchase as a percent of conversion shares		100.00%
Series A Convertible Preferred Stock
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)			5,000,000	5,000,000	8,000
Preferred shares issued (in shares)			8,000	0
Dividend paid in-kind to preferred stockholders			$ 300
Series A Convertible Preferred Stock | 2017 Private Placement
Class of Stock [Line Items]
Shares issued upon conversion (in shares)		429
Proceeds for issuance of preferred stock, gross	$ 8,000	$ 1,300
Dividend rate, preferred stock		4.00%
Dividend rate, period of initial rate		5 years
Increased dividend rate, preferred stock		8.00%
Risk-free interest rate		3.15%
Credit spread		31.27%
Market yield		34.42%
Proceeds from beneficial conversion feature		$ 3,700
Deemed dividend on preferred stock			4,100
Ownership percentage, convertible preferred stock		70.00%
Units | 2017 Private Placement
Class of Stock [Line Items]
Number of units issued		8,000
Purchase price per unit (in usd per share)		$ 1,000
Warrants
Class of Stock [Line Items]
Discount on shares, preferred stock		$ 3,000
Deemed dividend on preferred stock			$ 300