DEBT - Schedule of Long-term Debt (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Total debt obligations	$ 3,332.6	$ 3,291.6
Unamortized debt issuance costs	(26.6)	(28.0)
Unamortized original issuance discount, net	(48.0)	(40.8)
Carrying value of debt	3,258.0	3,222.8
Less current portion	(29.6)	(30.2)
Long-term debt less current portion	3,228.4	3,192.6
US Term Loan
Debt Instrument [Line Items]
Unamortized debt issuance costs	(9.5)	(9.9)
Unamortized original issuance discount, net	(32.8)	(34.2)
EMEA Term loan due 2025
Debt Instrument [Line Items]
Unamortized debt issuance costs	(2.4)	(2.7)
Unamortized original issuance discount, net	(26.8)	(18.7)
7.875% Senior unsecured notes due 2024
Debt Instrument [Line Items]
Unamortized debt issuance costs	(11.8)	(12.3)
Unamortized original issuance discount, net	11.6	12.1
Term loan \| US Term Loan
Debt Instrument [Line Items]
Total debt obligations	1,739.0	1,743.5
Term loan \| EMEA Term loan due 2025
Debt Instrument [Line Items]
Total debt obligations	$ 951.5	828.8
Senior Notes \| 7.875% Senior unsecured notes due 2024
Debt Instrument [Line Items]
Stated percentage rate	7.875%
Total debt obligations	$ 575.0	575.0
Other secured loans
Debt Instrument [Line Items]
Total debt obligations	2.1	4.3
Revolving line of credit due 2023
Debt Instrument [Line Items]
Total debt obligations	65.0
Revolving line of credit due 2023 \| Line of Credit
Debt Instrument [Line Items]
Total debt obligations	$ 65.0	$ 140.0

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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