Investments and Fair Value Measurements (Details 2) (USD $)
9 Months Ended 12 Months Ended
Sep. 30, 2012
Dec. 31, 2011
Summary of estimated fair value of the warrant liability    
Stock price $ 1.11 $ 0.65
Strike price $ 2.50 $ 2.50
Remaining contractual term (years) 3 years 3 months 18 days 4 years 1 month 6 days
Volatility 192.20% 215.50%
Adjusted volatility 125.80% 125.50%
Risk-free rate 0.40% 0.60%
Dividend yield 0.00% 0.00%