INDEBTEDNESS - Summary of Long-term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Total	$ 313.2	$ 450.3
Less: Current maturities of long-term debt	14.6	17.1
Less: Unamortized debt issuance costs	3.4	4.3
Long-term debt	295.2	428.9
Revolving credit facility
Debt Instrument [Line Items]
Total	61.0	138.5
U.S. term loan
Debt Instrument [Line Items]
Total	196.2	228.1
Multi-currency term loans
Debt Instrument [Line Items]
Total	$ 56.0	$ 83.7

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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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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