Contractual interest rate for funds borrowed, under the debt agreement.

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Debt - Partial Redemption of 4.125% Senior Secured Notes - Additional Information (Detail) € in Thousands, $ in Millions				3 Months Ended		9 Months Ended
	Oct. 12, 2018 USD ($)	Oct. 12, 2018 EUR (€)	Oct. 09, 2018 EUR (€)	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)	Apr. 30, 2019
Debt Instrument [Line Items]
Loss on extinguishment of debt \| $				$ 4	$ 7	$ 7	$ 31
4.125% Senior Secured Notes due 2024 \| Acquisition Corp.
Debt Instrument [Line Items]
Due date of senior secured notes	2024	2024				2024
Redemptions of senior notes		€ 34,500	€ 34,500
Interest rate		4.125%	4.125%	4.125%		4.125%
Senior notes redemption price		€ 36,170
Redemption price, percentage of principal amount redeemed	103.00%	103.00%
Debt instrument remaining outstanding amount		€ 310,500
Loss on extinguishment of debt \| $	$ 2
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]
Interest rate			3.625%	3.625%		3.625%		3.625%