CONDENSED CONSOLIDATED STATEMENT OF STOCKHOLDERS' EQUITY (USD $)	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit during Development Stage [Member]
Balance at Dec. 31, 2012	$ 25,916,150	$ 6,708	$ 240,970,852	$ (215,061,410)
Balance (in shares) at Dec. 31, 2012		67,075,779
Stock-based compensation	1,448,294	0	1,448,294	0
Common stock issued pursuant to exercise of stock options	141,012	8	141,004	0
Common stock issued pursuant to exercise of stock options (in shares)		81,875
Common stock issued under at-the-market equity offering program at an average sales price of approximately $3.06 per share	2,781,604	95	2,781,509	0
Common stock issued under at-the-market equity offering program at an average sales price of approximately $3.06 per share (in shares)		952,306
Net loss	(11,095,786)	0	0	(11,095,786)
Balance at Sep. 30, 2013	$ 19,191,274	$ 6,811	$ 245,341,659	$ (226,157,196)
Balance (in shares) at Sep. 30, 2013		68,109,960