Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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

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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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Subsequent Events (Details)									3 Months Ended			9 Months Ended
Subsequent Events (Details)	Aug. 01, 2020	Jul. 14, 2020 USD ($)	Jul. 07, 2020 shares	Jun. 30, 2020 USD ($) shares	Jun. 30, 2020 EUR (€)	Jun. 29, 2020 USD ($)	Jun. 29, 2020 EUR (€)	Oct. 12, 2018 EUR (€)	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($) shares	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($) shares	Jun. 30, 2019 USD ($)	Aug. 04, 2020 shares	Jun. 30, 2020 EUR (€) shares	Jun. 29, 2020 EUR (€)	Jun. 16, 2020	Jun. 05, 2020 shares	Feb. 28, 2020 shares	Sep. 30, 2019 USD ($) shares	Sep. 30, 2019 EUR (€) shares	Oct. 09, 2018 USD ($)
Subsequent Event [Line Items]
Loss on extinguishment of debt										$ 0	$ 4,000,000	$ 0	$ 7,000,000
Acquisition Corp.
Subsequent Event [Line Items]
Face or principal amount of debt instrument				$ 3,019,000,000.000						$ 3,019,000,000.000		$ 3,019,000,000.000								$ 2,998,000,000
4.125% Senior Secured Notes due 2024
Subsequent Event [Line Items]
Interest rate				4.125%						4.125%	4.125%	4.125%	4.125%		4.125%
4.125% Senior Secured Notes due 2024 \| Acquisition Corp.
Subsequent Event [Line Items]
Interest rate				4.125%				4.125%		4.125%		4.125%			4.125%							4.125%
Face or principal amount of debt instrument				$ 349,000,000						$ 349,000,000		$ 349,000,000			€ 311,000,000					340,000,000	€ 311,000,000
Redemptions of senior notes \| €					€ 311,000,000			€ 34,500,000
Senior notes redemption price \| €								€ 36,170,000
Redemption price, percentage of principal amount redeemed								103.00%
Loss on extinguishment of debt													$ 2,000,000
4.875% Senior Secured Notes due 2024
Subsequent Event [Line Items]
Interest rate				4.875%						4.875%	4.875%	4.875%	4.875%		4.875%
4.875% Senior Secured Notes due 2024 \| Acquisition Corp.
Subsequent Event [Line Items]
Interest rate				4.875%						4.875%		4.875%			4.875%							4.875%
Face or principal amount of debt instrument				$ 220,000,000						$ 220,000,000		$ 220,000,000								220,000,000		$ 30,000,000
Redemptions of senior notes				$ 220,000,000
Loss on extinguishment of debt													$ 1,000,000
5.000% Senior Secured Notes due 2023 \| Acquisition Corp.
Subsequent Event [Line Items]
Interest rate				5.00%						5.00%		5.00%			5.00%		5.00%
Face or principal amount of debt instrument				$ 300,000,000						$ 300,000,000		$ 300,000,000								$ 300,000,000
Redemptions of senior notes				$ 244,000,000
Class A Common Stock
Subsequent Event [Line Items]
Shares outstanding (in shares) \| shares				77,000,000						77,000,000		77,000,000			77,000,000			77,000,000		0	0
Shares issued (in shares) \| shares				77,000,000						77,000,000		77,000,000			77,000,000					0	0
Class B Common Stock
Subsequent Event [Line Items]
Shares outstanding (in shares) \| shares				433,000,000						433,000,000		433,000,000			433,000,000			433,000,000	510,000,000	505,830,022	505,830,022
Shares issued (in shares) \| shares				433,000,000						433,000,000		433,000,000			433,000,000					505,830,022	505,830,022
Subsequent Event \| 5.000% Senior Secured Notes due 2023 \| Acquisition Corp.
Subsequent Event [Line Items]
Redemptions of senior notes		$ 295,000
Subsequent Event \| Class A Common Stock
Subsequent Event [Line Items]
Shares outstanding (in shares) \| shares														88,550,000
Shares issued (in shares) \| shares														88,550,000
Subsequent Event \| Class A Common Stock \| Over-Allotment Option
Subsequent Event [Line Items]
Number of shares issued in transaction (in shares) \| shares			11,550,000
Subsequent Event \| Class B Common Stock
Subsequent Event [Line Items]
Shares outstanding (in shares) \| shares														421,450,000
Shares issued (in shares) \| shares														421,450,000
Senior Notes \| 3.875% Senior Secured Notes due 2030 \| Acquisition Corp.
Subsequent Event [Line Items]
Interest rate				3.875%		3.875%				3.875%		3.875%			3.875%	3.875%
Face or principal amount of debt instrument						$ 535,000,000
Senior Notes \| 2.750% Senior Secured Notes due 2028 \| Acquisition Corp.
Subsequent Event [Line Items]
Interest rate				2.75%		2.75%				2.75%		2.75%			2.75%	2.75%
Face or principal amount of debt instrument \| €																€ 325,000,000
Senior Notes \| 4.125% Senior Secured Notes due 2024 \| Acquisition Corp.
Subsequent Event [Line Items]
Interest rate				4.125%		4.125%				4.125%		4.125%			4.125%	4.125%
Redemptions of senior notes \| €					€ 311,000,000		€ 311,000,000
Senior notes redemption price \| €															€ 322,000,000
Redemption price, percentage of principal amount redeemed				103.094%	103.094%
Senior Notes \| 4.875% Senior Secured Notes due 2024 \| Acquisition Corp.
Subsequent Event [Line Items]
Interest rate				4.875%		4.875%				4.875%		4.875%			4.875%	4.875%
Redemptions of senior notes				$ 220,000,000		$ 220,000,000
Senior notes redemption price				$ 230,000,000						$ 230,000,000		$ 230,000,000
Redemption price, percentage of principal amount redeemed				103.656%	103.656%
Senior Notes \| 5.000% Senior Secured Notes due 2023 \| Acquisition Corp.
Subsequent Event [Line Items]
Interest rate				5.00%		5.00%				5.00%		5.00%			5.00%	5.00%	5.00%
Face or principal amount of debt instrument				$ 300,000,000		$ 300,000,000				$ 300,000,000		$ 300,000,000
Redemptions of senior notes				$ 244,000,000		$ 244,000,000						$ 569,000,000
Senior Notes \| 5.000% Senior Secured Notes due 2023 \| Acquisition Corp. \| Forecast
Subsequent Event [Line Items]
Loss on extinguishment of debt									$ 7,000,000
Senior Notes \| 4.125% Senior Secured Notes and 4.875% Senior Secured Notes \| Acquisition Corp. \| Forecast
Subsequent Event [Line Items]
Loss on extinguishment of debt									$ 23,000,000
Senior Notes \| Subsequent Event \| 5.000% Senior Secured Notes due 2023 \| Acquisition Corp.
Subsequent Event [Line Items]
Redemption price, percentage of principal amount redeemed	101.25%