XML 65 R50.htm IDEA: XBRL DOCUMENT v3.10.0.1
Stock-Based Compensation - Summary of Activity Relating to Stock Options (Detail) - USD ($)
$ / shares in Units, $ in Thousands
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Ending balance, Outstanding Shares 232,244  
Stock Options [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Beginning balance, Outstanding Shares 5,586,593  
Granted, Shares 3,103,494  
Exercised, Shares (767,147)  
Forfeited, Shares (392,173)  
Ending balance, Outstanding Shares 7,530,767 5,586,593
Vested and expected to vest, Shares 6,254,429  
Exercisable, Shares 2,846,158  
Beginning balance, Outstanding Weighted Average Exercise Price $ 43.58  
Granted, Weighted Average Exercise Price 164.50  
Exercised, Weighted Average Exercise Price 34.67  
Forfeited, Weighted Average Exercise Price 64.74  
Ending balance, Outstanding Weighted Average Exercise Price 93.22 $ 43.58
Vested and expected to vest, Weighted Average Exercise Price 85.55  
Exercisable, Weighted Average Exercise Price $ 40.69  
Outstanding, Weighted Average Remaining Life 8 years 10 days 8 years 2 months 26 days
Vested and expected to vest, Weighted Average Remaining Life 7 years 10 months 9 days  
Exercisable, Weighted Average Remaining Life 6 years 8 months 15 days  
Outstanding, Aggregate Intrinsic Value $ 227,447 $ 676,717
Vested and expected to vest, Aggregate Intrinsic Value 209,356  
Exercisable, Aggregate Intrinsic Value $ 159,799