Long-term Debt (Schedule of Long-term Debt) (Details) - USD ($) $ in Millions	Jun. 30, 2021	Jun. 30, 2020	Jan. 31, 2018
Debt Instrument [Line Items]
Principal Balance	$ 2,791.3	$ 3,045.4
Unamortized Discount and Debt Issuance Costs	(45.3)	(59.5)
Carrying Value	2,746.0	2,985.9
Current portion of long-term debt, principal balance	(4.1)	(4.1)
Current portion of long-term debt, unamortized discount and debt issuance costs	0.0	0.0
Current portion of long-term debt, carrying value	(4.1)	(4.1)
Long-term debt, principal balance	2,787.2	3,041.3
Long-term debt, unamortized discount and debt issuance costs	(45.3)	(59.5)
Long-term debt, carrying value	$ 2,741.9	$ 2,981.8
Senior Unsecured Notes \| 6.875% senior notes, due February 1, 2026
Debt Instrument [Line Items]
Stated interest rate	6.875%	6.875%	6.875%
Principal Balance	$ 1,022.9	$ 1,272.9
Unamortized Discount and Debt Issuance Costs	(12.7)	(18.7)
Carrying Value	1,010.2	1,254.2
Senior Secured Notes \| 6.500% senior notes, due July 1, 2025
Debt Instrument [Line Items]
Principal Balance	300.0	300.0
Unamortized Discount and Debt Issuance Costs	(4.0)	(5.0)
Carrying Value	296.0	295.0
Variable-rate credit facility \| Variable-rate credit facility \| Senior credit facility term loan, due 1/31/2025
Debt Instrument [Line Items]
Principal Balance	1,062.5	1,062.5
Unamortized Discount and Debt Issuance Costs	(10.4)	(13.1)
Carrying Value	1,052.1	1,049.4
Variable-rate credit facility \| Variable-rate credit facility \| Senior credit facility incremental term loan, due January 31, 2025
Debt Instrument [Line Items]
Principal Balance	405.9	410.0
Unamortized Discount and Debt Issuance Costs	(18.2)	(22.7)
Carrying Value	387.7	387.3
Variable-rate credit facility \| Variable-rate credit facility \| Revolving credit facility of $350 million, due January 31, 2023
Debt Instrument [Line Items]
Principal Balance	0.0	0.0
Unamortized Discount and Debt Issuance Costs	0.0	0.0
Carrying Value	$ 0.0	$ 0.0

Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net, Current Maturities

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Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net, Excluding Current Maturities

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Long-Term Debt, Gross, Current Maturities

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

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