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Amount, after accumulated amortization, of debt premium.

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LONG-TERM DEBT (Summary of Long-Term Debt) (Details) - USD ($) $ in Millions	Sep. 30, 2018	Jun. 30, 2018	Jul. 05, 2017	Apr. 10, 2017	Jan. 27, 2017	Jan. 19, 2017
Debt Instrument [Line Items]
Debt obligations	$ 5,741.8	$ 5,743.1
Less current portion	(5.0)	(5.0)
Long-term debt, less current portion	5,691.3	5,690.1
6.00% Senior Notes due 2023 [Member]
Debt Instrument [Line Items]
Debt obligations	1,430.0	1,430.0
Unamortized debt issuance costs	$ (57.1)	(59.6)
Interest rate	6.00%
6.375% Senior Notes due 2025 [Member]
Debt Instrument [Line Items]
Debt obligations	$ 900.0	900.0
Carrying value of debt	$ 5,696.3	5,695.1
Interest rate	6.375%
5.75% Senior Unsecured Notes due 2027 [Member]
Debt Instrument [Line Items]
Debt obligations	$ 1,650.0	1,650.0	$ 300.0	$ 550.0	$ 800.0
Less current portion	$ (5.0)	(5.0)
Interest rate	5.75%
Term Loan Facility
Debt Instrument [Line Items]
Debt obligations						$ 2,500.0
Unamortized premium, net	$ 11.6	11.6
Carrying value of debt	1,750.6	1,751.3
Term Loan Facility due 2021 [Member]
Debt Instrument [Line Items]
Debt obligations	492.5	493.8
Term Loan Facility due 2024 [Member]
Debt Instrument [Line Items]
Debt obligations	$ 1,269.3	$ 1,269.3