Consolidated Statement of Changes in Stockholders' Equity - USD ($) $ in Thousands	Series D Preferred Stock [Member]	Common Stock [Member]	Additional Paid-In Capital [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Income [Member]	Accumulated Deficit [Member]	Total
Balance at Dec. 31, 2016			$ 221,960	$ (22)		$ (209,299)	$ 12,639
Balance, shares at Dec. 31, 2016		7,606,518
Net loss						(10,353)	(10,353)
Unrealized gain on currency translation adjustment					354		354
Issuance of common stock in connection with: Underwritten offering, net of offering costs			4,479				4,479
Issuance of common stock in connection with: Underwritten offering, net of offering costs, shares		3,310,978
Issuance of common stock in connection with: Exercise of common stock warrants			2,124				2,124
Issuance of common stock in connection with: Exercise of common stock warrants, shares		1,062,113
Issuance of common stock in connection with: Payments made in stock (payroll and consultants)			3,042				3,042
Issuance of common stock in connection with: Payments made in stock (payroll and consultants), shares		1,772,152
Issuance of common stock in connection with: Compensation awards previously accrued			295				295
Issuance of common stock in connection with: Compensation awards previously accrued, shares		104,218
Issuance of common stock in connection with: Commitment agreement with Lincoln Park			302				302
Issuance of common stock in connection with: Commitment agreement with Lincoln Park, shares		192,431
Issuance of common stock in connection with: Conversion of amounts due to related parties			490				490
Issuance of common stock in connection with: Conversion of amounts due to related parties, shares		294,573
Issuance of common stock in connection with: Satisfaction of interest due on convertible promissory notes			270				270
Issuance of common stock in connection with: Satisfaction of interest due on convertible promissory notes, shares		137,742
Stock-based compensation			2,209				2,209
Issuance of Series D Preferred stock	$ 5,000
Issuance of Series D Preferred stock, shares	5,000,000
Issuance of common stock in connection with the conversion of Series D Preferred stock	$ (5,000)		648				648
Issuance of common stock in connection with the conversion of Series D Preferred stock, shares	(5,000,000)	416,667
Balance at Dec. 31, 2017			235,819	(22)	354	(219,652)	16,499
Balance, shares at Dec. 31, 2017		14,897,392
Net loss						(14,873)	(14,873)
Unrealized gain on currency translation adjustment					(79)		(79)
Issuance of common stock in connection with: Payments made in stock (payroll and consultants)			1,793				1,793
Issuance of common stock in connection with: Payments made in stock (payroll and consultants), shares		2,083,136
Issuance of common stock in connection with: Compensation awards previously accrued			19				19
Issuance of common stock in connection with: Compensation awards previously accrued, shares		12,232
Issuance of common stock in connection with: Conversion of amounts due to related parties			240				240
Issuance of common stock in connection with: Conversion of amounts due to related parties, shares		429,585
Issuance of common stock in connection with: Satisfaction of interest due on convertible promissory notes			180				180
Issuance of common stock in connection with: Satisfaction of interest due on convertible promissory notes, shares		276,796
Stock-based compensation			3,728				3,728
Satisfaction of convertible promissory notes			2,339				2,339
Satisfaction of convertible promissory notes, shares		775,184
Beneficial conversion feature			284				284
Procurement fee for debt instrument			160				160
Procurement fee for debt instrument, shares		302,655
Balance at Dec. 31, 2018			$ 244,562	$ (22)	$ 275	$ (234,525)	$ 10,290
Balance, shares at Dec. 31, 2018		18,776,980