XML 11 R39.htm IDEA: XBRL DOCUMENT v2.4.0.6
Stock-Based Compensation (Details)
3 Months Ended 6 Months Ended
Jun. 30, 2012
Jun. 30, 2011
Jun. 30, 2012
Jun. 30, 2011
Summary of assumptions used to estimate the fair value of stock options        
Risk-free interest rate (minimum) 0.32% 1.16% 0.37% 1.16%
Risk-free interest rate (maximum)   1.72%   1.89%
Expected volatility 122.00% 134.00% 131.00% 134.00%
Expected life in years 3 years 6 months 4 years 4 years 4 years
Dividend yield            
Forfeiture rate 8.00% 11.00% 8.00% 11.00%