Debt - Schedule of Long-term Debt (Details) - USD ($)	Mar. 31, 2025	Sep. 30, 2024
Debt Instrument [Line Items]
Premium less unamortized discount and unamortized DFCs	$ (30,000,000)	$ (34,000,000)
Total long-term debt, including the current portion, net	4,292,000,000	4,014,000,000
Unamortized discount	(9,000,000)	0
Acquisition Corp.
Debt Instrument [Line Items]
Total debt, including the current portion	4,020,000,000	4,048,000,000
Total long-term debt, including the current portion, net	3,990,000,000	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	$ 352,000,000	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	$ 481,000,000	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	2,000,000	2,000,000
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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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount of unamortized debt discount (premium) and debt issuance costs.

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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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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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