Stockholders' Equity (Details 3)
12 Months Ended
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
Stockholders Equity [Line Items]      
Annual dividend 0.00% 0.00% 0.00%
Minimum [Member]
     
Stockholders Equity [Line Items]      
Expected life (in years) 3 years 2 years 2 years
Risk free interest rate 0.29% 0.24% 0.25%
Expected volatility 65.10% 55.50% 66.90%
Maximum [Member]
     
Stockholders Equity [Line Items]      
Expected life (in years) 6 years 6 months 4 years 3 years 6 months
Risk free interest rate 2.43% 0.65% 1.39%
Expected volatility 77.50% 77.40% 75.40%