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 |