v3.21.2
Share-based Compensation - Summary of Option Activity (Detail)
$ / shares in Units, $ in Millions
12 Months Ended
Sep. 30, 2021
USD ($)
$ / shares
shares
Aggregate Intrinsic Value  
Stock price used to calculate aggregate intrinsic value (in dollars per share) $ 222.75
Stock Option  
Options  
Beginning balance (in shares) | shares 5,786,549
Granted (in shares) | shares 1,022,430
Forfeited (in shares) | shares (57,107)
Expired (in shares) | shares 0
Exercised (in shares) | shares (912,093)
Ending balance (in shares) | shares 5,839,779
Options exercisable at September 30, 2021 (in shares) | shares 3,736,509
Options exercisable and expected to vest at September 30, 2021 (in shares) | shares 5,783,092
Weighted- Average Exercise Price Per Share  
Beginning balance (in dollars per share) $ 114.61
Granted (in dollars per share) 207.57
Forfeited (in dollars per share) 179.38
Expired (in dollars per share) 0
Exercised (in dollars per share) 87.06
Ending balance (in dollars per share) 134.56
Options exercisable at September 30, 2021 (in dollars per share) 105.05
Options exercisable and expected to vest at September 30, 2021 (in dollars per share) $ 133.93
Weighted- Average Remaining Contractual Term (in years)  
Outstanding at September 30, 2021 6 years 6 months 21 days
Options exercisable at September 30, 2021 5 years 6 months 18 days
Options exercisable and expected to vest at September 30, 2021 6 years 6 months 14 days
Aggregate Intrinsic Value  
Outstanding at September 30, 2021 | $ $ 515
Options exercisable at September 30, 2021 | $ 440
Options exercisable and expected to vest at September 30, 2021 | $ $ 514