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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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Debt - Debt Capitalization (Narrative) (Details) $ in Millions	Sep. 30, 2025 USD ($)	Sep. 30, 2024 USD ($)	Nov. 30, 2023
Revolving Credit Facility \| Line of Credit
Short-Term Debt [Line Items]
Debt instrument, covenant, total indebtedness to EBITDA ratio	3.50
Acquisition Corp.
Short-Term Debt [Line Items]
Total debt, including the current portion	$ 4,090	$ 4,048
Acquisition Corp. \| Revolving Credit Facility
Short-Term Debt [Line Items]
Total debt, including the current portion	0	0
Debt instrument, covenant, total indebtedness to EBITDA ratio			3.60
Senior Term Loan Credit Agreement \| Acquisition Corp.
Short-Term Debt [Line Items]
Total debt, including the current portion	1,295
2.750% Senior Secured Notes due 2028 \| Acquisition Corp.
Short-Term Debt [Line Items]
Total debt, including the current portion	$ 381	363
Interest rate (as a percent)	2.75%
3.750% Senior Secured Notes \| Acquisition Corp.
Short-Term Debt [Line Items]
Total debt, including the current portion	$ 540	540
Interest rate (as a percent)	3.75%
3.875% Senior Secured Notes due 2030 \| Acquisition Corp.
Short-Term Debt [Line Items]
Interest rate (as a percent)	3.875%
2.250% Senior Secured Notes due 2031 \| Acquisition Corp.
Short-Term Debt [Line Items]
Total debt, including the current portion	$ 522	497
Interest rate (as a percent)	2.25%
3.000% Senior Secured Notes due 2031 \| Acquisition Corp.
Short-Term Debt [Line Items]
Total debt, including the current portion	$ 800	$ 800
Interest rate (as a percent)	3.00%