CONSOLIDATED STATEMENT OF CHANGES IN STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Preferred Stock [Member] Series B Convertible Preferred Stock [Member]	Preferred Stock [Member] Series C Convertible Preferred Stock [Member]	Common Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Income [Member]	Total	Series C Convertible Preferred Stock [Member]
Beginning balance at Dec. 31, 2015	$ 1	$ 0	$ 2	$ 223,323	$ (207,240)	$ 1	$ 16,087
Beginning balance (in shares) at Dec. 31, 2015	6,505	0	2,056,679
Stock-based compensation	$ 0	$ 0	$ 0	113	0	0	113
Conversion of convertible preferred stock into common stock	$ 0	$ 0	$ 0	0	0	0	0
Conversion of convertible preferred stock into common stock (in shares)	(505)	0	39,337
Conversion of senior secured convertible debentures into common stock	$ 0	$ 0	$ 0	265	0	0	265
Conversion of senior secured convertible debentures into common stock (in shares)	0	0	70,882
Warrants issued in connection with debt	$ 0	$ 0	$ 0	47	0	0	47
Reclassification of warrant liability to stockholders' equity	0	0	0	1,541	0	0	1,541
Other comprehensive income (loss)	0	0	0	0	0	1	1
Net loss	0	0	0	0	(3,335)	0	(3,335)
Ending balance at Dec. 31, 2016	$ 1	$ 0	$ 2	225,289	(210,575)	2	14,719
Ending balance (in shares) at Dec. 31, 2016	6,000	0	2,166,898
Stock-based compensation	$ 0	$ 0	$ 0	186	0	0	186
Issuance of convertible preferred stock in exchange for convertible debentures	$ 0	$ 4	$ 0	25,906	0	0	25,910
Issuance of convertible preferred stock in exchange for convertible debentures (in shares)	0	40,482	0
Conversion of convertible preferred stock into common stock	$ (1)	$ 0	$ 2	0	0	0	1
Conversion of convertible preferred stock into common stock (in shares)	(6,000)	(4,300)	2,066,182
Conversion of senior secured convertible debentures into common stock	$ 0	$ 0	$ 0	262	0	0	262
Conversion of senior secured convertible debentures into common stock (in shares)	0	0	70,000
Issuance of common stock for fractional shares in reverse stock split (in shares)			1,345
Other comprehensive income (loss)						(2)	(2)
Net loss	$ 0	$ 0	$ 0	0	(18,831)	0	(18,831)	$ (11,084)
Ending balance at Dec. 31, 2017	$ 0	$ 4	$ 4	$ 251,643	$ (229,406)	$ 0	$ 22,245
Ending balance (in shares) at Dec. 31, 2017	0	36,182	4,304,425