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Warrant Liability (Details 1) (USD $)
 3 Months Ended 3 Months Ended 12 Months Ended
Mar. 31, 2013
Mar. 31, 2012
Dec. 31, 2012
Mar. 31, 2013
Warrant agreement 2009 [Member]
Dec. 31, 2012
Warrant agreement 2009 [Member]
Assumptions used for the Black-Scholes option pricing model          
Expected life (years)       2 years 1 month 6 days 2 years 3 months 18 days
Risk-free interest rate       0.30% 0.30%
Expected volatility       98.60% 94.50%
Expected dividend yield       0.00% 0.00%
Fair value of warrant liability $ 9,035,131   $ 9,265,365 $ 68,320 $ 63,340
Change in fair value of warrant liability $ (188,607) $ (4,941,177)   $ 4,980