Long-Term Debt (Summary of Long-Term Debt) (Details) - USD ($) $ in Millions	Mar. 31, 2017	Jun. 30, 2016
Debt Instrument [Line Items]
Debt obligations	$ 5,630.0	$ 4,167.4
Unamortized debt issuance costs	(75.7)	(53.8)
Carrying value of debt	5,523.8	4,085.3
Less current portion	(25.0)
Long-term debt, less current portion	5,498.8	4,085.3
6.00% Senior Notes due 2023 [Member]
Debt Instrument [Line Items]
Debt obligations	1,430.0	1,430.0
Unamortized premium	$ 5.7	6.3
Interest rate	6.00%
6.375% Senior Notes due 2025 [Member]
Debt Instrument [Line Items]
Debt obligations	$ 900.0	900.0
Unamortized discount	$ (14.6)	(15.6)
Interest rate	6.375%
5.75% Senior Unsecured Notes due 2027 [Member]
Debt Instrument [Line Items]
Debt obligations	$ 800.0
Interest rate	5.75%
Term Loan Facility [Member]
Debt Instrument [Line Items]
Unamortized discount	$ (21.6)	(19.0)
Carrying value of debt	2,478.4	1,818.4
Term Loan Facility due 2021 [Member]
Debt Instrument [Line Items]
Debt obligations	500.0	$ 1,837.4
Term Loan Facility due 2024 [Member]
Debt Instrument [Line Items]
Debt obligations	$ 2,000.0

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
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-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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-SubTopic 30
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