Debt - Minimum Repayments Long Term Debt (Details) $ in Millions |
Dec. 31, 2017
USD ($)
|
|---|---|
| Debt Instrument [Line Items] | |
| 2018 | $ 51.9 |
| 2019 | 46.1 |
| 2020 | 43.2 |
| 2021 | 40.2 |
| 2022 | 406.7 |
| Later years | 614.5 |
| Total | 1,202.6 |
| Capital leases | |
| Debt Instrument [Line Items] | |
| 2018 | 22.6 |
| 2019 | 18.4 |
| 2020 | 16.7 |
| 2021 | 15.0 |
| 2022 | 12.8 |
| Later years | 11.4 |
| Total | 96.9 |
| Other long-term debt | |
| Debt Instrument [Line Items] | |
| 2018 | 29.3 |
| 2019 | 27.7 |
| 2020 | 26.5 |
| 2021 | 25.2 |
| 2022 | 393.9 |
| Later years | 603.1 |
| Total | $ 1,105.7 |