DEBT - Schedule of Long-term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Long term debt, gross	$ 3,291.6	$ 3,270.9
Unamortized debt issuance costs	(28.0)	(31.6)	$ (33.8)
Unamortized original issuance discount, net	(40.8)	(47.8)	9.3
Carrying value of debt	3,222.8	3,191.5
Less current portion	(30.2)	(39.9)
Long-term debt less current portion	3,192.6	3,151.6
Other secured loans
Debt Instrument [Line Items]
Long term debt, gross	4.3	18.1
US Term loan
Debt Instrument [Line Items]
Unamortized debt issuance costs	(9.9)	(11.5)	(14.7)
Unamortized original issuance discount, net	(34.2)	(39.8)	(6.5)
US Term loan \| Term loan
Debt Instrument [Line Items]
Long term debt, gross	1,743.5	1,761.2
EMEA Term loan
Debt Instrument [Line Items]
Unamortized debt issuance costs	(2.7)	(3.2)	0.0
Unamortized original issuance discount, net	(18.7)	(22.0)	$ 0.0
EMEA Term loan \| Term loan
Debt Instrument [Line Items]
Long term debt, gross	828.8	857.6
Revolving line of credit
Debt Instrument [Line Items]
Long term debt, gross	140.0
Revolving line of credit \| Revolving line of credit
Debt Instrument [Line Items]
Long term debt, gross	$ 140.0	$ 59.0

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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