v2.4.0.8
Warrants (Details) (Warrant [Member])
12 Months Ended
Dec. 31, 2013
Dec. 31, 2012
Warrant [Member]
   
Weighted-average assumptions were utilized in the fair value calculations for warrants granted    
Expected dividend yield 0.00% 0.00%
Expected stock price volatility, minimum 93.00% 105.00%
Expected stock price volatility, maximum 108.00% 113.00%
Risk-free interest rate, minimum 0.14% 2.06%
Risk-free interest rate, maximum 2.60% 3.03%
Expected life of warrants, minimum 1 month 6 days 7 years 3 months 18 days
Expected life of warrants, maximum 9 years 1 month 6 days 9 years 9 months 18 days