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Debt - Schedule of Long-term Debt (Detail)	Jun. 30, 2023 USD ($)	Jun. 30, 2023 EUR (€)	Jan. 27, 2023 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2022 EUR (€)	Jun. 30, 2022
Debt Instrument [Line Items]
Total long-term debt, including the current portion	$ 4,028,000,000			$ 3,773,000,000
Issuance premium less unamortized discount and unamortized deferred financing costs	(40,000,000)			(41,000,000)
Total long-term debt, including the current portion, net	$ 3,988,000,000			3,732,000,000
3.750% Senior Secured Notes due 2029
Debt Instrument [Line Items]
Interest rate	3.75%	3.75%				3.75%
Acquisition Corp. \| Senior Term Loan Facility due 2023
Debt Instrument [Line Items]
Total long-term debt, including the current portion	$ 1,295,000,000			$ 1,145,000,000
Acquisition Corp. \| 2.750% Senior Secured Notes due 2028
Debt Instrument [Line Items]
Interest rate	2.75%	2.75%		2.75%	2.75%
Face or principal amount of debt instrument \| €		€ 325,000,000			€ 325,000,000
Total long-term debt, including the current portion	$ 354,000,000			$ 318,000,000
Acquisition Corp. \| 3.750% Senior Secured Notes due 2029
Debt Instrument [Line Items]
Interest rate	3.75%	3.75%		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	3.875%	3.875%		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 due 2031
Debt Instrument [Line Items]
Interest rate	2.25%	2.25%		2.25%	2.25%
Face or principal amount of debt instrument \| €		€ 445,000,000			€ 445,000,000
Total long-term debt, including the current portion	$ 485,000,000			$ 435,000,000
Acquisition Corp. \| 3.000% Senior Secured Notes due 2031
Debt Instrument [Line Items]
Interest rate	3.00%	3.00%		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	19,000,000			0
Acquisition Corp. \| Revolving Credit Facility
Debt Instrument [Line Items]
Total long-term debt, including the current portion	0			0
Commitments under revolving credit facility	300,000,000			300,000,000
Letters of credit outstanding	4,000,000			4,000,000
Revolving credit facility outstanding	$ 0			$ 0