ENVIRONMENTAL (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | |||
|---|---|---|---|---|---|
Sep. 30, 2016 |
Sep. 30, 2015 |
Sep. 30, 2016 |
Sep. 30, 2015 |
Dec. 31, 2015 |
|
| Environmental Remediation Obligations [Abstract] | |||||
| Reserves for future environmental expenditures - total | $ 137.5 | $ 139.9 | $ 137.5 | $ 139.9 | $ 138.1 |
| Reserves for environmental expenditures - noncurrent | 118.5 | 120.9 | 118.5 | 120.9 | $ 119.1 |
| Environmental Remediation Expense | $ 0.4 | $ 7.3 | $ 5.5 | $ 13.1 | |