Liquidity and Going Concern - Narrative (Details) $ in Thousands			1 Months Ended	3 Months Ended			9 Months Ended		12 Months Ended
	Oct. 24, 2017 USD ($) shares	Jul. 31, 2017 USD ($)	Nov. 13, 2017 USD ($)	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($) offering shares	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($) offering shares	Sep. 30, 2016 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2016 USD ($) shares	Dec. 31, 2015 USD ($)
Line of Credit Facility [Line Items]
Cash					$ 1,439	$ 1,343	$ 1,439	$ 1,343		$ 1,140	$ 1,764
Working capital					696		696
Restricted cash					18		18			$ 18
Net income					$ 7,104	$ (1,705)	5,846	(3,021)
Net cash provided by operating activities							1,073	265
Cash paid during the period for interest payments on indebtedness							777	841
Extinguishment of debt and accrued interest		$ 9,362
Principal payment made							$ 341	$ 400
Registered direct offering, convertible, shares issued (in shares) | shares					32		32			32
Number of possible future equity offerings (or more) | offering					1		1
Series B-1 Preferred Stock
Line of Credit Facility [Line Items]
Registered direct offering, convertible, shares issued (in shares) | shares					0		0
Subsequent Event | Series B-1 Preferred Stock
Line of Credit Facility [Line Items]
Registered direct offering, convertible, shares issued (in shares) | shares	2,800
Gross proceeds from issuance of stock	$ 2,800
Estimated net proceeds from issuance of stock	$ 2,325
Western Alliance Bank | Subsequent Event
Line of Credit Facility [Line Items]
Principal payment made			$ 200
Super G Capital
Line of Credit Facility [Line Items]
Cash paid during the period for interest payments on indebtedness					$ 46
Principal payment made					$ 4
Required principal and interest payments		$ 1,540
Scenario, Forecast | Western Alliance Bank
Line of Credit Facility [Line Items]
Required principal payments									$ 400
Scenario, Forecast | Super G Capital
Line of Credit Facility [Line Items]
Required principal and interest payments				$ 152					$ 823