| **Long-term Debt - Long-term Debt Outstanding (Details) - USD ($) $ in Millions**                  | Dec. 31, 2016 | Mar. 31, 2016 | Dec. 31, 2015 | Nov. 18, 2013 | Sep. 11, 2012 |
|----------------------------------------------------------------------------------------------------|---------------|---------------|---------------|---------------|---------------|
| **Schedule of Outstanding Long-term Debt**                                                         |          |          |          |          |          |
| Capital lease obligations                                                                          | $ 279.3       |          | $ 288.2       |          |          |
| Total debt and Capital lease obligations                                                           | 3,016.4       |          | 3,171.5       |          |          |
| Less: Current portion                                                                              | (37.1)        |          | (36.8)        |          |          |
| Long-term debt, net of current portion                                                             | 2,979.3       |          | 3,134.7       |          |          |
| Term Loan Facilities [Member] | Term Loan Facilities [Member]                                      |          |          |          |          |          |
| **Schedule of Outstanding Long-term Debt**                                                         |          |          |          |          |          |
| Total debt                                                                                         | $ 421.2       |          | $ 443.3       |          |          |
| Senior Notes [Member] | 7.75% Senior Notes Due 2022 [Member]                                       |          |          |          |          |          |
| **Schedule of Outstanding Long-term Debt**                                                         |          |          |          |          |          |
| Debt instrument interest rate (percent)                                                            | 7.75%         |          | 7.75%         |          |          |
| Total debt                                                                                         | $ 0.0         |          | $ 174.3       |          |          |
| Senior Notes [Member] | 5.125% Senior Notes Due 2023 [Member]                                      |          |          |          |          |          |
| **Schedule of Outstanding Long-term Debt**                                                         |          |          |          |          |          |
| Debt instrument interest rate (percent)                                                            | 5.125%        | 5.125%        | 5.125%        |          |          |
| Total debt                                                                                         | $ 295.3       |          | $ 294.6       |          |          |
| Senior Notes [Member] | 5.75% Senior Notes Due 2024 [Member]                                       |          |          |          |          |          |
| **Schedule of Outstanding Long-term Debt**                                                         |          |          |          |          |          |
| Debt instrument interest rate (percent)                                                            | 5.75%         |          | 5.75%         |          | 5.75%         |
| Total debt                                                                                         | $ 1,193.2     |          | $ 1,192.6     |          |          |
| Senior Notes [Member] | 5.75% Senior Notes Due 2025 [Member]                                       |          |          |          |          |          |
| **Schedule of Outstanding Long-term Debt**                                                         |          |          |          |          |          |
| Debt instrument interest rate (percent)                                                            | 5.75%         | 5.75%         | 5.75%         |          |          |
| Total debt                                                                                         | $ 343.9       |          | $ 343.4       |          |          |
| Senior Subordinated Notes [Member] | 2.00% Convertible Senior Subordinated Notes due 2043 [Member] |          |          |          |          |          |
| **Schedule of Outstanding Long-term Debt**                                                         |          |          |          |          |          |
| Debt instrument interest rate (percent)                                                            | 2.00%         |          | 2.00%         | 2.00%         |          |
| Total debt                                                                                         | $ 275.7       |          | $ 265.9       |          |          |
| Other Notes Payable [Member]                                                                       |          |          |          |          |          |
| **Schedule of Outstanding Long-term Debt**                                                         |          |          |          |          |          |
| Total debt                                                                                         | 55.8          |          | 39.2          |          |          |
| Revolving Credit Facility [Member]                                                                 |          |          |          |          |          |
| **Schedule of Outstanding Long-term Debt**                                                         |          |          |          |          |          |
| Total debt                                                                                         | $ 152.0       |          | $ 130.0       |          |          |

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| - Definition
Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.
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| - Definition
Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.
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| - Definition
Contractual interest rate for funds borrowed, under the debt agreement.
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| - Definition
Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.
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| - Definition
Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.
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Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.
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