Statements of Changes in Stockholders' Equity (USD $)	Total	Private Placement	Consultants	Common Stock	Common Stock Private Placement	Common Stock Consultants	Additional Paid-In Capital	Additional Paid-In Capital Private Placement	Additional Paid-In Capital Consultants	Accumulated Deficit
Beginning Balance at Dec. 31, 2008	$ 22,832,551			$ 231			$ 112,627,957			$ (89,795,637)
Beginning Balance (in shares) at Dec. 31, 2008				2,309,799
Issuance of stock (in shares)					1,469,420	8,333
Issuance of stock		17,218,021	97,500		147	1		17,217,874	97,499
Issuance of stock from stock option plans (in shares)				2,073
Issuance of stock from stock option plans	23,671						23,671
Other issuances of stock from option plan (in shares)				18,318
Other issuances of stock from option plan	164,632			2			164,630
Stock-based compensation expense	2,035,335						2,035,335
Issuance of common stock under employee stock purchase plan (in shares)				20,335
Issuance of common stock under employee stock purchase plan	80,525			2			80,523
Warrants fair value adjustment	5,175,136						5,175,136
Net loss	(11,917,500)									(11,917,500)
Ending Balance at Dec. 31, 2009	35,709,871			383			137,422,625			(101,713,137)
Ending Balance (in shares) at Dec. 31, 2009				3,828,278
Issuance of stock from stock option plans (in shares)				978
Issuance of stock from stock option plans	10,273						10,273
Other issuances of stock from option plan (in shares)				17,538
Other issuances of stock from option plan	22,843			2			22,841
Stock-based compensation expense	1,184,570						1,184,570
Issuance of common stock under employee stock purchase plan (in shares)				19,462
Issuance of common stock under employee stock purchase plan	162,563			2			162,561
Net loss	(16,891,148)									(16,891,148)
Ending Balance at Dec. 31, 2010	20,198,972			387			138,802,870			(118,604,285)
Ending Balance (in shares) at Dec. 31, 2010				3,866,256
Other issuances of stock from option plan (in shares)				14,050
Other issuances of stock from option plan				1			(1)
Stock-based compensation expense	837,040						837,040
Issuance of common stock under employee stock purchase plan (in shares)				24,014
Issuance of common stock under employee stock purchase plan	33,614			2			33,612
Net loss	(9,981,105)									(9,981,105)
Ending Balance at Dec. 31, 2011	$ 11,088,521			$ 390			$ 139,673,521			$ (128,585,390)
Ending Balance (in shares) at Dec. 31, 2011				3,904,320