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Debt - Schedule of Long-term Debt (Details) € in Millions	Sep. 30, 2024 USD ($)	Sep. 30, 2024 EUR (€)	Nov. 30, 2023 USD ($)	Nov. 29, 2023 USD ($)	Sep. 30, 2023 USD ($)	Jan. 27, 2023 USD ($)	Sep. 30, 2022
Debt Instrument [Line Items]
Total long-term debt, including the current portion	$ 4,048,000,000				$ 4,002,000,000
Issuance premium less unamortized discount and unamortized deferred financing costs	(34,000,000)				(38,000,000)
Total long-term debt, including the current portion, net	$ 4,014,000,000				$ 3,964,000,000
3.750% Senior Secured Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	3.75%	3.75%			3.75%		3.75%
Acquisition Corp. \| Senior Term Loan Facility due 2031
Debt Instrument [Line Items]
Total long-term 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 (as a percent)	2.75%	2.75%
Face or principal amount of debt instrument \| €		€ 325
Total long-term debt, including the current portion	$ 363,000,000				343,000,000
Acquisition Corp. \| 3.750% Senior Secured Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	3.75%	3.75%
Total long-term 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 (as a percent)	3.875%	3.875%
Total long-term debt, including the current portion	$ 535,000,000				535,000,000
Acquisition Corp. \| 2.250% Senior Secured Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	2.25%	2.25%
Face or principal amount of debt instrument \| €		€ 445
Total long-term debt, including the current portion	$ 497,000,000				471,000,000
Acquisition Corp. \| 3.000% Senior Secured Notes due 2031
Debt Instrument [Line Items]
Interest rate (as a percent)	3.00%	3.00%
Total long-term debt, including the current portion	$ 800,000,000				800,000,000
Acquisition Corp. \| Term Loan Mortgage
Debt Instrument [Line Items]
Face or principal amount of debt instrument						$ 19,000,000
Total long-term debt, including the current portion	18,000,000				18,000,000
Acquisition Corp. \| Revolving Credit Facility
Debt Instrument [Line Items]
Total long-term debt, including the current portion	0				0
Line of credit facility, current borrowing capacity	350,000,000		$ 350,000,000	$ 300,000,000	350,000,000
Letters of credit outstanding	0				2,000,000
Revolving credit facility outstanding	$ 0				$ 0