Long-term Debt - Schedule of Long-Term Debt (Details) - USD ($)	Sep. 30, 2018	Jun. 30, 2018
Principal Balance
Principal balance of long-term debt, including current maturities	$ 2,995,500,000	$ 3,195,500,000
Current portion of long-term debt	0	(18,000,000)
Principal balance of long-term debt, excluding current maturities	2,995,500,000	3,177,500,000
Unamortized Discount and Debt Issuance Costs
Unamortized discount and debt issuance costs, including current maturities	(58,100,000)	(59,900,000)
Current portion of long-term debt	0	300,000
Unamortized discount and debt issuance costs, excluding current maturities	(58,100,000)	(59,600,000)
Carrying Value
Long-term debt, including current maturities	2,937,400,000	3,135,600,000
Current portion of long-term debt	0	(17,700,000)
Carrying value of long-term debt, excluding current maturities	2,937,400,000	3,117,900,000
Senior Notes \| 6.875% senior notes, due 2/1/2026
Principal Balance
Principal balance of long-term debt, including current maturities	1,400,000,000	1,400,000,000
Unamortized Discount and Debt Issuance Costs
Unamortized discount and debt issuance costs, including current maturities	(25,800,000)	(26,500,000)
Carrying Value
Long-term debt, including current maturities	$ 1,374,200,000	$ 1,373,500,000
Debt instrument, stated interest rate	6.875%	6.875%
Variable-rate credit facilities \| Line of Credit \| Senior credit facility term loan, due 1/31/2025
Principal Balance
Principal balance of long-term debt, including current maturities	$ 1,595,500,000	$ 1,795,500,000
Unamortized Discount and Debt Issuance Costs
Unamortized discount and debt issuance costs, including current maturities	(32,300,000)	(33,400,000)
Carrying Value
Long-term debt, including current maturities	1,563,200,000	1,762,100,000
Variable-rate credit facilities \| Line of Credit \| Revolving credit facility of $350 million, due 1/31/2023
Principal Balance
Principal balance of long-term debt, including current maturities	0	0
Unamortized Discount and Debt Issuance Costs
Unamortized discount and debt issuance costs, including current maturities	0	0
Carrying Value
Long-term debt, including current maturities	0	0
Maximum borrowing capacity	$ 350,000,000	$ 350,000,000

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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Long-Term Debt, Gross, Excluding Current Maturities

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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

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Amount of unamortized debt discount (premium) and debt issuance costs.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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