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Debt and Financing Arrangements - Schedule of Debt (Details) € in Millions, $ in Millions	Mar. 31, 2024 USD ($)	Mar. 31, 2024 EUR (€)	Sep. 30, 2023 USD ($)	Mar. 31, 2023
Long-term debt:
Less: debt issuance costs	$ (31)		$ (31)
Gross long-term debt	2,535		2,533
Less: current portion	134		132
Net long-term debt	2,401		2,401
Short-term debt:
Other bank borrowings	0		2
Total short-term debt	0		2
Term Loan B due in 2031
Long-term debt:
Long-term debt, gross	$ 635		635
Unsecured debt \| 8.25% Notes due 2031
Long-term debt:
Interest rate	8.25%	8.25%
Long-term debt, gross	$ 500		500
Unsecured debt \| 4.875% Notes due in 2026
Long-term debt:
Interest rate	4.875%	4.875%
Long-term debt, gross	$ 795		795
Unsecured debt \| 3.50% Notes due in 2024
Long-term debt:
Interest rate	3.50%	3.50%		3.50%
Long-term debt, gross	$ 133	€ 123	130
Unsecured debt \| Other bank borrowings and finance lease obligations
Long-term debt:
Long-term debt, gross	$ 3		4
Term Loan \| 7.00% Secured Notes due 2028
Long-term debt:
Interest rate	7.00%	7.00%
Long-term debt, gross	$ 500		$ 500