Convertible Promissory Notes (Details) (USD $)
In Millions, except Share data, unless otherwise specified
1 Months Ended 9 Months Ended
Nov. 30, 2011
Sep. 30, 2012
Jun. 30, 2011
5% Convertible Promissory Notes [Member]
Cash [Member]
Jun. 30, 2011
5% Convertible Promissory Notes [Member]
Global rights [Member]
Jun. 30, 2011
5% Convertible Promissory Notes [Member]
Pfizer [Member]
May 31, 2011
5% Convertible Promissory Notes [Member]
Existing investors [Member]
Convertible Promissory Notes (Textual) [Abstract]            
Notes issued     $ 8.0 $ 7.0 $ 15.0 $ 20.0
Convertible Promissory Notes (Additional Textual) [Abstract]            
Notes accrued maturity date   May 25, 2012        
Conversion of notes into common stock 2,757,788          
Notes accrued interest rate   5.00%