Debt and Other Obligations - Schedule of Long-Term Obligations (Detail) - USD ($) $ in Millions	Sep. 30, 2025	Sep. 30, 2024
Debt Instrument [Line Items]
Total variable rate debt	$ 130	$ 113
Medium Term Notes	8	8
Debt	1,092
Total debt	962	962
Finance lease obligations (Note R)	30	27
Unamortized debt issuance costs and debt discount	(6)	(7)
Total debt	1,116	1,095
Less Current portion of long-term debt	260	8
Total long-term debt	856	1,087
Revolving Credit Facility - Euro, expires fiscal 2027 [Member]
Debt Instrument [Line Items]
Line of credit	130	113
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	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 2026, 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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