| **Long-term Debt**             | 3 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
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| **Debt Disclosure [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| Long-term Debt                 | Long-term DebtOur long-term debt outstanding consists of the following (in millions): March 31, 2016 December 31, 2015Credit Agreement—   Advances under revolving credit facility$130.0 $130.0Term loan facilities437.8 443.3Bonds payable—   7.75% Senior Notes due 2022124.8 174.35.125% Senior Notes due 2023294.8 294.65.75% Senior Notes due 20241,192.7 1,192.65.75% Senior Notes due 2025343.5 343.42.00% Convertible Senior Subordinated Notes due 2043268.3 265.9Other notes payable38.4 39.2Capital lease obligations285.9 288.2 3,116.2 3,171.5Less: Current portion(36.6) (36.8)Long-term debt, net of current portion$3,079.6 $3,134.7The following chart shows scheduled principal payments due on long-term debt for the next five years and thereafter (in millions): Face Amount Net AmountApril 1 through December 31, 2016$27.8 $27.8201736.5 36.5201836.6 36.6201939.6 39.62020813.7 760.4202110.1 10.1Thereafter2,225.4 2,205.2Total$3,189.7 $3,116.2On February 23, 2016, we gave notice of, and made an irrevocable commitment for, the redemption of$50 millionof the outstanding principal amount of ourexisting 7.75% Senior Notes due 2022 (the “2022 Notes”). On March 24, 2016, we completed this redemptionusing cash on hand and capacity under our revolving credit facility. Pursuant to the terms of the 2022 Notes, this optional redemption was made at a price of103.875%, which resulted in a total cash outlay of approximately$52 million. As a result of this redemption, we recorded a$2.4 millionLoss on early extinguishment of debtin the first quarter of 2016.On April 6, 2016, we gave notice of, and made an irrevocable commitment for, the redemption of an additional $50 million of the outstanding principal amount of the 2022 Notes. This optional redemption also will be made at a price of 103.875%, which will result in a total cash outlay of approximately $52 million when the transaction closes on May 6, 2016. We plan to use cash on hand and capacity under our revolving credit facility to fund the redemption. As a result of this redemption, we expect to record an approximate$2 millionloss on early extinguishment of debt in the second quarter of 2016.For additional information regarding our indebtedness, see Note 8, Long-term Debt, to the consolidated financial statements accompanying the 2015 Form 10-K. |

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No definition available.
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| - Definition
The entire disclosure for long-term debt.
+ References
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
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