Fair Value Measurements (Carrying Values And Fair Values Of Assets and Liabilities Not Required to be Carried at Fair Value on a Recurring Basis) (Details) - USD ($) $ in Millions	Jun. 30, 2017	Mar. 31, 2017
Senior Notes \| 5.875% Senior Notes
Fair Value, Carrying Values and Fair Values of Assets and Liabilities Not Required to be Carried at Fair Value on a Recurring Basis [Line Items]
Coupon rate	5.875%
Convertible Senior Subordinated Notes
Fair Value, Carrying Values and Fair Values of Assets and Liabilities Not Required to be Carried at Fair Value on a Recurring Basis [Line Items]
Coupon rate	1.25%
Convertible Senior Subordinated Notes \| April 2013 Notes
Fair Value, Carrying Values and Fair Values of Assets and Liabilities Not Required to be Carried at Fair Value on a Recurring Basis [Line Items]
Coupon rate	1.25%
Carrying Value
Assets:
Investment in Pop's mandatorily redeemable preferred stock units	$ 96.3	$ 96.8
Liabilities:
Total liabilities, fair value disclosure	2,835.2	3,428.1
Carrying Value \| Term Loan \| Term Loan A Facility
Liabilities:
Loans, fair value disclosure	950.5	961.8
Carrying Value \| Term Loan \| Term Loan B Facility
Liabilities:
Loans, fair value disclosure	1,142.7	1,554.7
Carrying Value \| Senior Notes \| 5.875% Senior Notes
Liabilities:
Senior Notes, fair value disclosure	498.9	498.3
Carrying Value \| Convertible Senior Subordinated Notes \| April 2013 Notes
Liabilities:
Convertible notes, fair value disclosures	60.0	60.0
Carrying Value \| Production Loans \| Production Loans
Liabilities:
Loans, fair value disclosure	183.1	353.3
Fair Value \| Fair Value (Level 3)
Assets:
Investment in Pop's mandatorily redeemable preferred stock units	122.1	122.1
Fair Value \| Fair Value (Level 2)
Liabilities:
Total liabilities, fair value disclosure	2,934.3	3,548.2
Fair Value \| Fair Value (Level 2) \| Term Loan \| Term Loan A Facility
Liabilities:
Loans, fair value disclosure	961.6	983.8
Fair Value \| Fair Value (Level 2) \| Term Loan \| Term Loan B Facility
Liabilities:
Loans, fair value disclosure	1,182.3	1,610.0
Fair Value \| Fair Value (Level 2) \| Senior Notes \| 5.875% Senior Notes
Liabilities:
Senior Notes, fair value disclosure	548.0	542.1
Fair Value \| Fair Value (Level 2) \| Convertible Senior Subordinated Notes \| April 2013 Notes
Liabilities:
Convertible notes, fair value disclosures	59.0	58.5
Fair Value \| Fair Value (Level 2) \| Production Loans \| Production Loans
Liabilities:
Loans, fair value disclosure	$ 183.4	$ 353.8

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Fair value portion of borrowing which can be exchanged for a specified number of another security at the option of the issuer or the holder, for example, but not limited to, the entity's common stock.

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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Fair value portion of contractual obligation to pay money on demand or on fixed or determinable dates.

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