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.

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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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Long-Term Debt (Summary of Long-Term Debt) (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Jun. 30, 2014	May 16, 2014	Nov. 26, 2013
Debt Instrument [Line Items]
Debt obligations	$ 3,751.1us-gaap_DebtInstrumentCarryingAmount	$ 3,260.8us-gaap_DebtInstrumentCarryingAmount		$ 1,749.8us-gaap_DebtInstrumentCarryingAmount
Carrying value of debt	3,740.6us-gaap_LongTermDebt	3,240.2us-gaap_LongTermDebt	2,015.9us-gaap_LongTermDebt
Less current portion	(20.5)us-gaap_LongTermDebtCurrent	(20.5)us-gaap_LongTermDebtCurrent
Long-term debt, less current portion	3,720.1us-gaap_LongTermDebtNoncurrent	3,219.7us-gaap_LongTermDebtNoncurrent
Term Loan Facility due 2019 [Member] \| Credit Facility [Member]
Debt Instrument [Line Items]
Debt obligations	1,995.5	2,010.8
Unamortized discount on Term Loan Facility due 2019	(17.8)	(20.6)
Secured Debt [Member] \| 8.125% Senior Secured First Priority Notes due 2020 [Member]
Debt Instrument [Line Items]
Debt obligations		750.0
Unsecured Debt [Member] \| 10.125% Senior Unsecured Notes due 2020 [Member]
Debt Instrument [Line Items]
Debt obligations	325.6	500.0
6.00% Senior Unsecured Notes due 2023 [Member]
Debt Instrument [Line Items]
Debt obligations	1,430.0
Unamortized premium on 6.00% Senior Unsecured Notes due 2023	$ 7.3