Stockholders' Equity (Details 2) (USD $)
Sep. 30, 2013
Warrants  
Warrants to purchase common stock, number of shares 10,916,216
October 2012 Debt and Equity Financing Warrants
 
Warrants  
Warrants to purchase common stock, number of shares 10,700,926
Exercise Price (in dollars per share) $ 2.00
Common stock warrants expiring in 2017
 
Warrants  
Warrants to purchase common stock, number of shares 106,631
Exercise Price (in dollars per share) $ 2.79
Common stock warrants expiring in 2016
 
Warrants  
Warrants to purchase common stock, number of shares 108,659
Exercise Price (in dollars per share) $ 7.45