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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Debt - Additional Information (Detail) € in Millions			3 Months Ended		6 Months Ended
Debt - Additional Information (Detail) € in Millions	Jan. 27, 2023 USD ($)	Nov. 01, 2022 USD ($)	Mar. 31, 2023 USD ($)	Mar. 31, 2022 USD ($)	Mar. 31, 2023 USD ($)	Mar. 31, 2022 USD ($)	Mar. 31, 2023 EUR (€)	Sep. 30, 2022
Debt Instrument [Line Items]
Debt instrument, covenant, total indebtedness to EBITDA ratio			3.50		3.50		3.50
Interest expense, net			$ 35,000,000	$ 32,000,000	$ 67,000,000	$ 62,000,000
Interest Expense, Debt			$ 38,000,000	$ 32,000,000	$ 75,000,000	$ 61,000,000
Weighted-average interest rate of total debt			4.00%	3.30%	4.00%	3.30%	4.00%	3.50%
2.750% Senior Secured Notes due 2028 \| Acquisition Corp.
Debt Instrument [Line Items]
Interest rate			2.75%		2.75%		2.75%
Face or principal amount of debt instrument \| €							€ 325
3.875% Senior Secured Notes due 2030 \| Acquisition Corp.
Debt Instrument [Line Items]
Interest rate			3.875%		3.875%		3.875%
3.000% Senior Secured Notes due 2031 \| Acquisition Corp.
Debt Instrument [Line Items]
Interest rate			3.00%		3.00%		3.00%
3.750% Senior Secured Notes due 2029
Debt Instrument [Line Items]
Interest rate			3.75%	3.75%	3.75%	3.75%	3.75%
3.750% Senior Secured Notes due 2029 \| Acquisition Corp.
Debt Instrument [Line Items]
Interest rate			3.75%		3.75%		3.75%
2.250% Senior Secured Notes due 2031 \| Acquisition Corp.
Debt Instrument [Line Items]
Interest rate			2.25%		2.25%		2.25%
Face or principal amount of debt instrument \| €							€ 445
Senior Term Loan Facility \| Acquisition Corp.
Debt Instrument [Line Items]
Line of credit facility, increase		$ 150,000,000
Maximum commitments under the facility		$ 1,295,000,000
Term Loan Mortgage \| Acquisition Corp.
Debt Instrument [Line Items]
Face or principal amount of debt instrument	$ 19,000,000
Term Loan Mortgage \| Acquisition Corp. \| Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Debt instrument, marginal interest rate	1.40%
Senior Notes
Debt Instrument [Line Items]
Scheduled maturities of long-term debt in 2023			$ 0		$ 0
Scheduled maturities of long-term debt in 2024			0		0
Scheduled maturities of long-term debt in 2025			0		0
Scheduled maturities of long-term debt in 2026			0		0
Scheduled maturities of long-term debt, 2027			0		0
Scheduled maturities of long-term debt, 2028			354,000,000		354,000,000
Scheduled maturities of long-term debt, thereafter			$ 2,380,000,000		$ 2,380,000,000
Line of Credit \| Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument, covenant, total indebtedness to EBITDA ratio			3.50		3.50		3.50