XML 27 R40.htm IDEA: XBRL DOCUMENT v2.4.0.6
Stock-Based Compensation (Details)
3 Months Ended 9 Months Ended
Sep. 30, 2012
Sep. 30, 2011
Sep. 30, 2012
Sep. 30, 2011
Summary of assumptions used to estimate the fair value of stock options        
Risk-free interest rate (minimum) 0.33% 0.57% 0.36% 0.57%
Risk-free interest rate (maximum)   1.32%   1.89%
Expected volatility 129.00% 132.00% 131.00%  
Expected life in years 4 years 4 years 4 years 4 years
Dividend yield            
Forfeiture rate 8.00% 11.00% 8.00% 11.00%
Maximum [Member]
       
Summary of assumptions used to estimate the fair value of stock options        
Expected volatility       134.00%
Minimum [Member]
       
Summary of assumptions used to estimate the fair value of stock options        
Expected volatility       132.00%