Commitments and Contingencies - Guarantor Obligations (Details) $ in Millions	Sep. 30, 2020 USD ($)
Guarantor Obligations [Line Items]
Remainder of Fiscal 2021	$ 157
Fiscal 2022	412
Fiscal 2023 and Thereafter	572
Total	1,141
Surety bonds
Guarantor Obligations [Line Items]
Remainder of Fiscal 2021	38
Fiscal 2022	262
Fiscal 2023 and Thereafter	86
Total	386
Letters of credit
Guarantor Obligations [Line Items]
Remainder of Fiscal 2021	58
Fiscal 2022	135
Fiscal 2023 and Thereafter	462
Total	655
Stand-by letters of credit
Guarantor Obligations [Line Items]
Remainder of Fiscal 2021	61
Fiscal 2022	15
Fiscal 2023 and Thereafter	24
Total	$ 100