Consolidated Statements of Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Deficit [Member]	Total
Balances at Dec. 31, 2015	$ 4	$ 219,319	$ (213,591)	$ 5,732
Balances (in shares) at Dec. 31, 2015	4,450,994
Issuance of common stock to officer and directors	$ 1	1,451		1,452
Issuance of common stock to officer and directors (in shares)	323,155
Issuance of common stock, net of issuance costs	$ 7	10,125		$ 10,132
Issuance of common stock, net of issuance costs (in shares)	7,147,035			300,000
Issuance of common stock in settlement of litigation	$ 1	(1)
Issuance of common stock in settlement of litigation (in shares)	631,358
Issuance of common stock for services		198		198
Issuance of common stock for services (in shares)	65,000
Issuance of common stock upon exercise of options		10		10
Issuance of common stock upon exercise of options (in shares)	5,625
Issuance of common stock upon vesting of restricted stock units
Issuance of common stock upon vesting of restricted stock units (in shares)	3,750
Issuance of warrants in connection with acquisition of licenses		361		361
Issuance of warrants in exchange for services		40		40
Issuance of warrants in exchange for services (in shares)
Conversion of notes payable and related accrued interest and fees to common stock	$ 2	3,385		3,387
Conversion of notes payable and related accrued interest and fees to common stock (in shares)	2,350,480
Beneficial conversion feature		484		484
Issuance of stock in connection with financing agreement	1	(1)
Stock-based compensation expense		844		844
Write down in fair value of warrants
Comprehensive loss			(27,019)	(27,019)
Balances at Dec. 31, 2016	$ 15	236,216	(240,610)	(4,379)
Balances (in shares) at Dec. 31, 2016	14,977,397
Issuance of common stock, net of issuance costs				0
Issuance of common stock in settlement of litigation	$ 9,315	12		12
Issuance of warrants in exchange for services
Beneficial conversion feature				500
Issuance of stock in connection with financing agreement	9,315	12		12
Return of share of stock by advisor	(40,000)
Stock-based compensation expense		2,115		2,115
Write down in fair value of warrants		(97)		(97)
Comprehensive loss			(21,987)	(21,987)
Balances at Dec. 31, 2017	$ 15	$ 238,246	$ (262,597)	$ (24,336)
Balances (in shares) at Dec. 31, 2017	14,946,712