Share-based Compensation - Summary of Option Activity (Detail) $ / shares in Units, $ in Millions	12 Months Ended
	Sep. 30, 2022 USD ($) $ / shares shares
Aggregate Intrinsic Value
Stock price used to calculate aggregate intrinsic value (in dollars per share)	$ 177.65
Stock Option
Options
Beginning balance (in shares) | shares	5,839,779
Granted (in shares) | shares	961,570
Forfeited (in shares) | shares	(134,247)
Expired (in shares) | shares	(1,264)
Exercised (in shares) | shares	(497,214)
Ending balance (in shares) | shares	6,168,624
Options exercisable at September 30, 2022 (in shares) | shares	4,299,455
Options exercisable and expected to vest at September 30, 2022 (in shares) | shares	6,122,504
Weighted- Average Exercise Price Per Share
Beginning balance (in dollars per share)	$ 134.56
Granted (in dollars per share)	200.86
Forfeited (in dollars per share)	199.34
Expired (in dollars per share)	207.57
Exercised (in dollars per share)	104.15
Ending balance (in dollars per share)	145.92
Options exercisable at September 30, 2022 (in dollars per share)	122.49
Options exercisable and expected to vest at September 30, 2022 (in dollars per share)	$ 145.50
Weighted- Average Remaining Contractual Term (in years)
Outstanding at September 30, 2022	6 years 1 month 2 days
Options exercisable at September 30, 2022	5 years 1 month 20 days
Options exercisable and expected to vest at September 30, 2022	6 years 25 days
Aggregate Intrinsic Value
Outstanding at September 30, 2022 | $	$ 250
Options exercisable at September 30, 2022 | $	250
Options exercisable and expected to vest at September 30, 2022 | $	$ 250