CONDENSED CONSOLIDATED STATEMENT OF CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY (UNAUDITED) - 3 months ended Mar. 31, 2016 - USD ($) $ in Thousands	Common Stock	Additional Paid-In Capital	Accumulated Deficit	Total
Beginning Balance, Shares at Dec. 31, 2015	694,396
Beginning Balance, Amount at Dec. 31, 2015	$ 694	$ 229,456	$ (62,556)	$ 167,594
Exercise of common stock options, Shares	20
Exercise of common stock options, Amount		3		3
Stock-based compensation		719		719
Sale of common shares, Shares	9,812
Sale of common shares, Amount	$ 10	4,994		5,004
Unrealized gain on marketable securities				0
Exercise of warrants, Shares	27
Exercise of warrants, Amount		35		35
Net loss			(4,012)	(4,012)
Ending Balance, Shares at Mar. 31, 2016	704,255
Ending Balance, Amount at Mar. 31, 2016	$ 704	$ 235,207	$ (4,012)	$ 169,343