Commitments and Contingencies (Details) - USD ($) $ in Millions |
3 Months Ended | 12 Months Ended | |||
|---|---|---|---|---|---|
Jul. 16, 2018 |
Jun. 30, 2017 |
Dec. 31, 2017 |
Sep. 30, 2018 |
Dec. 31, 2016 |
|
| Loss Contingencies [Line Items] | |||||
| Collective bargaining agreement, term | 3 years | ||||
| Maximum exposure for other labor matters | $ 41.0 | $ 31.0 | |||
| Produquímica | |||||
| Loss Contingencies [Line Items] | |||||
| Contingent liabilities assumed | 10.5 | 7.9 | |||
| Cote Blanche | |||||
| Loss Contingencies [Line Items] | |||||
| Amount of potential payments | $ 7.4 | ||||
| Settlement amount | $ 7.7 | ||||
| Loss on litigation settlement | 0.0 | ||||
| Brazilian tax litigation and assessments | |||||
| Loss Contingencies [Line Items] | |||||
| Amount of potential payments | $ 18.1 | $ 15.4 |