Annual report pursuant to Section 13 and 15(d)

Stock Based Compensation (Details)

v2.4.0.6
Stock Based Compensation (Details) (USD $)
In Millions, except Share data in Thousands, unless otherwise specified
 12 Months Ended
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Stock option activity      
Number of Shares Underlying Options, Outstanding at beginning of period 3,805    
Number of Shares Underlying Options, Granted 1,024 1,169 1,565
Number of Shares Underlying Options, Exercised (759) (302) (1,014)
Number of Shares Underlying Options, Forfeited (5)    
Number of Shares Underlying Options, Outstanding at end of period 4,065 3,805  
Number of Shares Underlying Options, Vested - end of period 3,153    
Number of Shares Underlying Options, Vested and expected to vest - end of period 3,781    
Weighted Average Exercise Price Per Share, Outstanding at beginning of period $ 5.10    
Weighted Average Exercise Price Per Share, Granted $ 8.81    
Weighted Average Exercise Price Per Share, Exercised $ 4.62 $ 4.12 $ 4.28
Weighted Average Exercise Price Per Share, Forfeited $ 8.33    
Weighted Average Exercise Price Per Share, Outstanding at end of period $ 6.12 $ 5.10  
Weighted Average Exercise Price Per Share, Vested - end of period $ 5.53    
Weighted Average Exercise Price Per Share, Vested and expected to vest - end of period $ 6.12    
Weighted Average Remaining Contractual Term, Outstanding at beginning of period 2 years 7 months 24 days 2 years 11 months 9 days  
Weighted Average Remaining Contractual Term, Granted 4 years 2 months 16 days    
Weighted Average Remaining Contractual Term, Exercised 1 year 3 months 15 days    
Weighted Average Remaining Contractual Term, Forfeited 3 years 11 months 12 days    
Weighted Average Remaining Contractual Term, Outstanding at end of period 2 years 7 months 24 days 2 years 11 months 9 days  
Weighted Average Remaining Contractual Term, Vested at end of period 2 years 3 months 22 days    
Weighted Average Remaining Contractual Term, Vested and expected to vest - end of period 2 years 7 months 24 days    
Aggregate Intrinsic Value, Outstanding at end of period $ 8.62    
Aggregate Intrinsic Value, Vested - end of period 8.26    
Aggregate Intrinsic Value, Vested and expected to vest - end of the period $ 8.51