SHAREHOLDERS' EQUITY (Details) (USD $)	12 Months Ended									1 Months Ended		12 Months Ended				1 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2011 Board of Directors [Member]	Dec. 31, 2010 Board of Directors [Member]	Dec. 31, 2009 Board of Directors [Member]	Dec. 31, 2011 Board of Directors [Member] Selling, General and Adminstrative Expense [Member]	Dec. 31, 2010 Board of Directors [Member] Selling, General and Adminstrative Expense [Member]	Dec. 31, 2009 Board of Directors [Member] Selling, General and Adminstrative Expense [Member]	Jan. 31, 2011 Employees and Non-Employee Members of Scientific Advisory Board [Member]	Jan. 31, 2010 Employees and Non-Employee Members of Scientific Advisory Board [Member]	Dec. 31, 2010 Employees and Non-Employee Members of Scientific Advisory Board [Member] Selling, General and Adminstrative Expense [Member]	Dec. 31, 2009 Employees and Non-Employee Members of Scientific Advisory Board [Member] Selling, General and Adminstrative Expense [Member]	Dec. 31, 2010 Employees and Non-Employee Members of Scientific Advisory Board [Member] Research and Development Expense [Member]	Dec. 31, 2009 Employees and Non-Employee Members of Scientific Advisory Board [Member] Research and Development Expense [Member]	Jan. 31, 2011 Employees [Member]	Jan. 31, 2010 Employees [Member]	Jan. 31, 2011 Non-Employee Members of Scientific Advisory Board [Member]	Jan. 31, 2010 Non-Employee Members of Scientific Advisory Board [Member]	Mar. 31, 2011 Common Stock [Member]
Class of Stock [Line Items]
Issuance of common stock through a public offering, net of expenses (in shares)																				5,750,000
Sale price of common stock (in dollars per share)																				$ 46.00
Proceeds from issuance of common stock through a public offering																				$ 249,628,814
Issuance of common stock through a public offering, expenses	14,871,186																			14,871,186
Deferred Compensation Arrangement with Employees and Non-Employees, Share-Based Payments [Line Items]
Shares issued (in shares)				20,000	23,036	22,260				59,472	127,995
Fair value of shares issued				788,000	284,725	205,905										1,768,493	1,513,710	299,943	299,979
Compensation charge							788,000	270,523	210,302			1,193,545	1,051,697	874,891	761,992
Accrued liability for compensation charge				28,138
Shares withheld for tax withholding obligations (in shares)																18,792	41,259
Fair value of shares withheld for tax withholding obligations																655,010	585,220
Common stock from warrant exercises (in shares)	586,972	677,826	61,024
Proceeds from warrant exercises	$ 7,397,710	$ 9,515,232	$ 618,783