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Long-Term Debt (Summary of Long-Term Debt) (Details) - USD ($) $ in Millions	Sep. 30, 2016	Jun. 30, 2016	Apr. 14, 2016
Debt Instrument [Line Items]
Debt obligations	$ 4,167.4	$ 4,167.4
Unamortized debt issuance costs	(52.1)	(53.8)
Carrying value of debt	$ 4,088.1	4,085.3
6.00% Senior Notes due 2023 [Member]
Debt Instrument [Line Items]
Interest rate	6.00%
6.375% Senior Notes due 2025 [Member]
Debt Instrument [Line Items]
Interest rate	6.375%
Term Loan Facility due 2021 [Member]
Debt Instrument [Line Items]
Debt obligations	$ 1,837.4	1,837.4
Unamortized discount	(18.0)	(19.0)
Carrying value of debt	1,819.4	1,818.4
Unsecured Debt [Member] \| 10.125% Senior Notes due 2020 [Member]
Debt Instrument [Line Items]
Interest rate			10.125%
Unsecured Debt [Member] \| 6.00% Senior Notes due 2023 [Member]
Debt Instrument [Line Items]
Debt obligations	1,430.0	1,430.0
Unamortized premium	6.1	6.3
Unsecured Debt [Member] \| 6.375% Senior Notes due 2025 [Member]
Debt Instrument [Line Items]
Debt obligations	900.0	900.0
Unamortized discount	$ (15.3)	$ (15.6)