ACCRUED LIABILITIES (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Accrued Liabilities, Current [Abstract]
Acquisition-related accruals	$ 0.0	$ 90.2
Accrued compensation and payroll taxes	77.8	53.4
Tax-related accruals	40.9	29.5
Accrued interest	30.7	35.0
Legal and professional costs	21.2	32.0
Accrued employee benefits	21.2	24.4
Environmental (current portion only)	17.0	19.0
Asset retirement obligation (current portion only)	12.6	7.3
Other	42.4	37.3
Accrued liabilities	$ 263.8	$ 328.1