v3.3.1.900
Employee Stock and Benefit Plans (Stock Option Activity) (Details) - USD ($)
$ / shares in Units, $ in Thousands
 12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Outstanding Shares        
Beginning balance (in shares) 7,605,407 7,039,093 6,513,508  
Granted (in shares) 1,526,450 2,744,150 2,001,400  
Exercised (in shares) (807,846) (1,216,710) (952,871)  
Canceled (in shares) (744,953) (961,126) (522,944)  
Ending balance (in shares) 7,579,058 7,605,407 7,039,093 6,513,508
Vested and Expected to vest (in shares) 7,111,282      
Exercisable (in shares) 5,195,339      
Weighted Average Exercise Price        
Weighted average exercise price, beginning balance (in dollars per share) $ 12.93 $ 7.17 $ 4.39  
Weighted average exercise price, granted (in dollars per share) 39.50 26.16 15.78  
Weighted average exercise price, exercised (in dollars per share) 12.50 6.28 4.32  
Weighted average exercise price, canceled (in dollars per share) 27.67 16.91 10.71  
Weighted average exercise price, ending balance (in dollars per share) 16.88 $ 12.93 $ 7.17 $ 4.39
Vested and Expected to vest, weighted average exercise price (in dollars per share) 15.69      
Exercisable, Weighted average exercise price (in dollars per share) $ 9.78      
Weighted Average Remaining Contractual Life (Years)        
Weighted average remaining contractual life 5 years 10 months 24 days 6 years 6 months 7 days 6 years 6 months 6 years 7 months 6 days
Vested and Expected to vest, weighted average remaining contractual life 5 years 8 months 12 days      
Exercisable, weighted average remaining contractual life 4 years 9 months 18 days      
Aggregate Intrinsic Value        
Aggregate intrinsic value $ 131,345 $ 188,743 $ 112,312 $ 67,711
Vested and Expected to vest, aggregate intrinsic value 130,208      
Exercisable, aggregate intrinsic value $ 121,098