Fair Value Measurements and Investments - Additional Information (Detail) - USD ($) $ in Millions	Sep. 30, 2022	Sep. 30, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total carrying value of debt	$ 22,450	$ 20,977
Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total carrying value of debt	22,500	21,000
Senior Notes | Estimate of Fair Value Measurement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value of debt	$ 19,900	$ 22,500