Debt and Other Obligations - Schedule of Long-Term Obligations (Detail) - USD ($) $ in Millions	Sep. 30, 2024	Sep. 30, 2023
Debt Instrument [Line Items]
Total variable rate debt	$ 113	$ 120
Medium Term Notes	8	8
Debt	1,075
Total debt	962	962
Finance lease obligations (Note S)	27	28
Unamortized debt issuance costs and debt discount	(7)	(8)
Total debt	1,095	1,102
Less current portion of long-term debt	(8)	(8)
Total long-term debt	1,087	1,094
Revolving Credit Facility - Euro, expires fiscal 2027 [Member]
Debt Instrument [Line Items]
Line of credit	113	120
3.4% Notes due fiscal 2026 [Member]
Debt Instrument [Line Items]
Notes	250	250
4.0% Notes due fiscal 2029 [Member]
Debt Instrument [Line Items]
Notes	300	300
5.0% Notes due fiscal 2032 [Member]
Debt Instrument [Line Items]
Notes		400
Medium Term Notes due fiscal 2028, 6.57% - 7.28% [Member]
Debt Instrument [Line Items]
Medium Term Notes	8	8
Chinese Renminbi Debt, Due Fiscal 2025, 4.3% [Member]
Debt Instrument [Line Items]
Debt	$ 4	$ 4

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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