DEBT - Schedule of Debt Issuance Costs and Discounts (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Debt Issuance Costs [Roll Forward]
Beginning balance	$ (31.6)	$ (33.8)
Debt issuance costs incurred	(1.2)	(8.7)
Amortization	4.8	4.4	$ 3.8
Loss on debt extinguishment		6.5
Ending balance	(28.0)	(31.6)	(33.8)
US Term loan
Debt Issuance Costs [Roll Forward]
Beginning balance	(11.5)	(14.7)
Debt issuance costs incurred	0.0	(4.7)
Amortization	1.6	1.8
Loss on debt extinguishment		6.1
Ending balance	(9.9)	(11.5)	(14.7)
EMEA Term loan
Debt Issuance Costs [Roll Forward]
Beginning balance	(3.2)	0.0
Debt issuance costs incurred	0.0	(3.4)
Amortization	0.5	0.2
Loss on debt extinguishment		0.0
Ending balance	(2.7)	(3.2)	0.0
Senior notes offering, December 2024
Debt Issuance Costs [Roll Forward]
Beginning balance	(14.3)	(16.1)
Debt issuance costs incurred	0.0	0.0
Amortization	2.0	1.8
Loss on debt extinguishment		0.0
Ending balance	(12.3)	(14.3)	(16.1)
Revolving Line of Credit
Debt Issuance Costs [Roll Forward]
Beginning balance	(2.6)	(3.0)
Debt issuance costs incurred	(1.2)	(0.6)
Amortization	0.7	0.6
Loss on debt extinguishment		0.4
Ending balance	$ (3.1)	$ (2.6)	$ (3.0)