Global LPG Business Transformation Initiatives (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Restructuring Cost and Reserve [Line Items]
Costs principally comprising consulting, advisory and employee-related costs			$ 87
Corporate Services Member
Restructuring Cost and Reserve [Line Items]
Costs principally comprising consulting, advisory and employee-related costs	$ 10	$ 9	$ 14