Annual report pursuant to Section 13 and 15(d)

Stock-based Compensation Plans and Awards - Schedule of stock option activity (Details)

v3.3.1.900
Stock-based Compensation Plans and Awards - Schedule of stock option activity (Details) - USD ($)
$ / shares in Units, $ in Thousands
 12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Outstanding Stock Options    
Granted (in shares) 2,940,736  
Stock options    
Outstanding Stock Options    
Balance at the beginning of the period (in shares) 10,980,256  
Granted (in shares) 2,940,736  
Exercised (in shares) (1,077,797)  
Forfeited (in shares) (27,304)  
Balance at the end of the period (in shares) 12,815,891 10,980,256
Vested and exercisable at the end of the period (in shares) 9,292,855  
Expected to vest at the end of the period (in shares) 3,259,020  
Weighted-Average Exercise Price    
Balance at the beginning of the period (in dollars per share) $ 7.91  
Granted (in dollars per share) 3.44  
Exercised (in dollars per share) 4.78  
Forfeited (in dollars per share) 6.09  
Balance at the end of the period (in dollars per share) 7.15 $ 7.91
Vested and exercisable at the end of the period (in dollars per share) 5.74  
Expected to vest at the end of the period (in dollars per share) $ 10.81  
Weighted-Average Remaining Contractual Term (in years)    
Outstanding at the beginning of the period 1 year 1 month 2 days 1 year 29 days
Outstanding at the end of the period 1 year 1 month 2 days 1 year 29 days
Vested and exercisable at the end of the period 6 months 26 days  
Expected to vest at the end of the period 2 years 5 months 19 days  
Aggregate Intrinsic Value    
Aggregate intrinsic value beginning of the period $ 101,151 $ 120,033
Aggregate intrinsic value end of the period 101,151 $ 120,033
Vested and exercisable at the end of the period 81,541  
Expected to vest at the end of the period $ 18,156