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Long-Term Debt (Summary of Long-Term Debt) (Details) - USD ($) $ in Millions	12 Months Ended		24 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Apr. 10, 2017	Jan. 27, 2017	Apr. 14, 2016
Debt Instrument [Line Items]
Debt obligations	$ 5,608.7	$ 4,167.4	$ 5,608.7
Unamortized debt issuance costs	(67.8)	(53.8)	(67.8)
Carrying value of debt	5,537.7	4,085.3	5,537.7
Less current portion	(5.0)		(5.0)
Long-term debt, less current portion	5,532.7	4,085.3	5,532.7
6.375% Senior Notes due 2025 [Member]
Debt Instrument [Line Items]
Debt obligations						$ 196.0
Unamortized discount						$ (15.9)
5.75% Senior Unsecured Notes due 2027 [Member]
Debt Instrument [Line Items]
Interest rate				5.75%	5.75%
Term Loan Facility
Debt Instrument [Line Items]
Unamortized discount	(16.0)	(19.0)	(16.0)
Carrying value of debt	1,912.7	1,818.4	1,912.7
Term Loan Facility due 2021 [Member]
Debt Instrument [Line Items]
Debt obligations	$ 498.8	$ 1,837.4	498.8
Maturity date	2021	2021
Term Loan Facility due 2024 [Member]
Debt Instrument [Line Items]
Debt obligations	$ 1,429.9		$ 1,429.9
Interest rate	2024.00%	2024.00%	2024.00%
Unsecured Notes \| 6.00% Senior Notes due 2023 [Member]
Debt Instrument [Line Items]
Debt obligations	$ 1,430.0	$ 1,430.0	$ 1,430.0
Unamortized premium	$ 5.5	$ 6.3	$ 5.5
Interest rate	6.00%	6.00%	6.00%
Maturity date	2023	2023
Unsecured Notes \| 6.375% Senior Notes due 2025 [Member]
Debt Instrument [Line Items]
Debt obligations	$ 900.0	$ 900.0	$ 900.0
Unamortized discount	$ (14.3)	$ (15.6)	$ (14.3)
Interest rate	6.375%	6.375%	6.375%
Maturity date	2025	2025
Unsecured Notes \| 5.75% Senior Unsecured Notes due 2027 [Member]
Debt Instrument [Line Items]
Debt obligations	$ 1,350.0		$ 1,350.0
Unamortized premium	$ 21.6		$ 21.6
Interest rate	5.75%	5.75%	5.75%
Maturity date			2027