Debt and Financing Arrangements - Short-Term Debt (Details) - USD ($) $ in Millions	Sep. 30, 2023	Sep. 30, 2022
Short-term Debt [Line Items]
Short-term debt	$ 385	$ 669
Weighted average interest rate on short-term debt outstanding	5.10%	0.50%
Bank borrowings
Short-term Debt [Line Items]
Short-term debt	$ 26	$ 10
Commercial paper
Short-term Debt [Line Items]
Short-term debt	200	172
Term loans
Short-term Debt [Line Items]
Short-term debt	$ 159	$ 487