Supplemental Financial Information - Accounts and Other Receivables (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Trade receivables	$ 117	$ 58
Credit card receivables	85	83
Business partners and other suppliers	478	432
Taxes receivable	133	699
Fuel hedging and receivables	34	8
Other	193	77
Accounts and other receivables	1,040	$ 1,357
Proceeds from Income Tax Refunds	$ 139