STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Deficit
Beginning Balance, shares at Dec. 31, 2013		2,240,794
Beginning Balance at Dec. 31, 2013	$ 15,581	$ 2	$ 90,512	$ (74,933)
Issuance of common stock for cash, net of offering costs, shares		730,890
Issuance of common stock for cash, net of offering costs	7,866	$ 1	7,865
Issuance of common stock upon exercise of warrants for cash, shares		29,861
Issuance of common stock upon exercise of warrants for cash, value	338		338
Issuance of common stock upon vesting of Restricted Stock Units, shares		19,953
Issuance of common stock upon vesting of Restricted Stock Units, value	(2)		(2)
Share-based compensation	647		647
Net loss	$ (9,689)			(9,689)
Ending Balance, shares at Dec. 31, 2014	3,021,498	3,021,498
Ending Balance at Dec. 31, 2014	$ 14,741	$ 3	99,360	(84,622)
Issuance of common stock for cash, net of offering costs, shares		6,003,082
Issuance of common stock for cash, net of offering costs	34,175	$ 6	34,169
Issuance of common stock upon vesting of Restricted Stock Units, shares		26,669
Issuance of common stock upon vesting of Restricted Stock Units, value	0	$ 0	0	0
Adjustment for fractional shares		(32)
Share-based compensation	599		599
Net loss	$ (11,445)			(11,445)
Ending Balance, shares at Dec. 31, 2015	9,051,217	9,051,217
Ending Balance at Dec. 31, 2015	$ 38,070	$ 9	$ 134,128	$ (96,067)