GOODWILL AND INTANGIBLE ASSETS (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	$ 216.5	$ 179.5	$ 231.7	$ 216.5	$ 179.5
Adjustments to intangibles through amortization expense			4.5	3.0	$ 4.9
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Asset			2.1	$ (0.3)
Finite-Lived Intangible Assets, Future Amortization Expense
Estimated amortization expense, 2013			223.0
Estimated amortization expense, 2014			215.3
Estimated amortization expense, 2015			209.0
Estimated amortization expense, 2016			203.4
Estimated amortization expense, 2017			199.8
Estimated amortization expense, Thereafter			$ 2,403.0