Debt and Financing Arrangements - Components of Net Financing Charges (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Debt Disclosure [Abstract]
Interest expense, net of capitalized interest costs	$ 54	$ 55	$ 165	$ 167
Other financing charges	6	7	16	19
Interest income	(2)	(1)	(5)	(7)
Net foreign exchange results for financing activities	(9)	(5)	(23)	(20)
Net financing charges	$ 49	$ 56	$ 153	$ 159