Debt - 3.625% Senior Secured Notes Offering - Additional Information (Detail)					9 Months Ended
	Nov. 05, 2018 USD ($)	Oct. 12, 2018 EUR (€)	Oct. 09, 2018 USD ($)	Oct. 09, 2018 EUR (€)	Jun. 30, 2019 USD ($)	Jun. 30, 2019 EUR (€)	Apr. 30, 2019 EUR (€)	Oct. 09, 2018 EUR (€)	Sep. 30, 2018 USD ($)	Sep. 30, 2018 EUR (€)	Jun. 30, 2018
Acquisition Corp.
Debt Instrument [Line Items]
Aggregate principal amount of debt instrument					$ 3,030,000,000				$ 2,851,000,000
3.625% Senior Secured Notes due 2026
Debt Instrument [Line Items]
Interest rate					3.625%	3.625%
3.625% Senior Secured Notes due 2026 | Acquisition Corp.
Debt Instrument [Line Items]
Aggregate principal amount of debt instrument | €							€ 195,000,000	€ 250,000,000
Interest rate			3.625%		3.625%	3.625%	3.625%	3.625%
4.125% Senior Secured Notes due 2024 | Acquisition Corp.
Debt Instrument [Line Items]
Aggregate principal amount of debt instrument					$ 353,000,000	€ 310,500,000			402,000,000	€ 345,000,000
Due date of senior secured notes		2024			2024
Interest rate		4.125%	4.125%		4.125%	4.125%		4.125%
Redemptions of senior notes | €		€ 34,500,000		€ 34,500,000
4.875% Senior Secured Notes due 2024
Debt Instrument [Line Items]
Interest rate					4.875%	4.875%					4.875%
4.875% Senior Secured Notes due 2024 | Acquisition Corp.
Debt Instrument [Line Items]
Aggregate principal amount of debt instrument			$ 30,000,000		$ 220,000,000				$ 250,000,000
Due date of senior secured notes			2024	2024	2024
Interest rate			4.875%		4.875%	4.875%		4.875%
5.625% Senior Secured Notes
Debt Instrument [Line Items]
Interest rate					5.625%	5.625%					5.625%
5.625% Senior Secured Notes | Acquisition Corp.
Debt Instrument [Line Items]
Due date of senior secured notes	2022				2022
Interest rate	5.625%		5.625%		5.625%	5.625%	5.625%	5.625%
Redemptions of senior notes	$ 26,550,000		$ 26,550,000