Debt - Schedule of Long-term Debt (Details) - USD ($)	Jun. 30, 2025	Sep. 30, 2024
Debt Instrument [Line Items]
Premium less unamortized discount and unamortized DFCs	$ (29,000,000)	$ (34,000,000)
Total long-term debt, including the current portion, net	4,363,000,000	4,014,000,000
Unamortized discount	(9,000,000)	0
Acquisition Corp.
Debt Instrument [Line Items]
Total debt, including the current portion	4,090,000,000	4,048,000,000
Total long-term debt, including the current portion, net	4,061,000,000	4,014,000,000
Acquisition Corp. \| Senior Term Loan Facility due 2031
Debt Instrument [Line Items]
Total debt, including the current portion	$ 1,295,000,000	1,295,000,000
Acquisition Corp. \| 2.750% Senior Secured Notes due 2028
Debt Instrument [Line Items]
Interest rate	2.75%
Total debt, including the current portion	$ 381,000,000	363,000,000
Acquisition Corp. \| 3.750% Senior Secured Notes due 2029
Debt Instrument [Line Items]
Interest rate	3.75%
Total debt, including the current portion	$ 540,000,000	540,000,000
Acquisition Corp. \| 3.875% Senior Secured Notes due 2030
Debt Instrument [Line Items]
Interest rate	3.875%
Total debt, including the current portion	$ 535,000,000	535,000,000
Acquisition Corp. \| 2.250% Senior Secured Notes due 2031
Debt Instrument [Line Items]
Interest rate	2.25%
Total debt, including the current portion	$ 522,000,000	497,000,000
Acquisition Corp. \| 3.000% Senior Secured Notes due 2031
Debt Instrument [Line Items]
Interest rate	3.00%
Total debt, including the current portion	$ 800,000,000	800,000,000
Acquisition Corp. \| Mortgage Term Loan due 2033
Debt Instrument [Line Items]
Total debt, including the current portion	17,000,000	18,000,000
Acquisition Corp. \| Revolving Credit Facility
Debt Instrument [Line Items]
Total debt, including the current portion	0	0
Commitments under revolving credit facility	350,000,000	350,000,000
Letters of credit outstanding	0	0
Revolving credit facility outstanding	0	0
Tempo
Debt Instrument [Line Items]
Total long-term debt, including the current portion, net	302,000,000	0
Tempo \| Tempo Asset-Based Notes due 2050
Debt Instrument [Line Items]
Total debt, including the current portion	$ 311,000,000	$ 0

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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