SUPPLEMENTARY DATA - QUARTERLY FINANCIAL DATA (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015
Schedule Of Quarterly Financial Information [Line Items]
Net revenues	$ 3,765	$ 218	$ 257	$ 224	$ 2,679	$ 210	$ 341	$ 5,357	$ 4,464	$ 8,587
Operating expenses	2,036	2,287	3,336	3,362	3,389	2,615	2,739	3,845	11,021	12,588
Operating (loss) income	1,729	(2,069)	(3,079)	(3,138)	(710)	(2,405)	(2,398)	1,512	(6,557)	(4,001)
Net (loss) income	$ 1,534	$ (2,250)	$ (3,288)	$ (3,384)	$ (916)	$ (2,649)	$ (2,663)	$ 1,239	$ (7,388)	$ (4,989)
Basic (loss) income per share	$ 0.13	$ (0.19)	$ (0.28)	$ (0.28)	$ (0.08)	$ (0.23)	$ (0.28)	$ 0.13	$ (0.62)	$ (0.46)
Diluted (loss) income per share	$ 0.13	$ (0.19)	$ (0.28)	$ (0.28)	$ (0.08)	$ (0.23)	$ (0.28)	$ 0.13	$ (0.62)	$ (0.46)