Long-Term Debt (Summary of Long-Term Debt) (Details) - USD ($) $ in Millions	Mar. 31, 2016	Jun. 30, 2015	May. 06, 2015
Debt Instrument [Line Items]
Debt obligations	$ 4,139.0	$ 3,752.4
Unamortized debt issuance costs	(66.2)	(71.0)
Carrying value of debt	4,057.3	3,668.7
Less current portion	(20.5)	(16.5)
Long-term debt, less current portion	4,036.8	3,652.2
Term Loan Facility due 2021 [Member]
Debt Instrument [Line Items]
Debt obligations	2,033.4	1,646.8
Unamortized discount on Term Loan Facility	(22.0)	(19.8)
Carrying value of debt	2,011.4	1,627.0
Unsecured Debt [Member]
Debt Instrument [Line Items]
Unamortized premium on 6.00% Senior Unsecured Notes	6.5	7.1
Unsecured Debt [Member] \| 10.125% Senior Notes due 2020 [Member]
Debt Instrument [Line Items]
Debt obligations	325.6	325.6
Unsecured Debt [Member] \| 6.00% Senior Notes due 2023 [Member]
Debt Instrument [Line Items]
Debt obligations	1,430.0	1,430.0
Unsecured Debt [Member] \| 6.375% Senior Notes due 2025 [Member]
Debt Instrument [Line Items]
Debt obligations	$ 350.0	$ 350.0	$ 344.5

Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

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 SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 20
-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef
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The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
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The amount of debt premium that was originally recognized at the issuance of the instrument that has yet to be amortized.

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-SubTopic 210
-Section S99
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-Subparagraph (SX 210.9-03.16)
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Amount of long-term debt, after unamortized discount or premium, scheduled 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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Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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