v2.4.0.6
Employee Stock and Benefit Plans - Fair Value Assumptions, Stock Options (Details) (Stock Options [Member])
3 Months Ended 9 Months Ended
Sep. 30, 2012
Sep. 30, 2011
Sep. 30, 2012
Sep. 30, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Expected term (in years)   5 years 7 months 6 days   5 years 7 months 6 days
Volatility 53.00% 55.00% 53.00% 55.00%
Dividend yield 0.00% 0.00% 0.00% 0.00%
Minimum [Member]
       
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Expected term (in years) 5 years 3 months 18 days   5 years 3 months 18 days  
Risk-free interest rate 0.60% 1.00% 0.60% 1.00%
Maximum [Member]
       
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Expected term (in years) 6 years   6 years  
Risk-free interest rate 0.70% 1.60% 0.80% 2.30%