INDEBTEDNESS - Summary of Long-term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Total long-term debt. gross	$ 450.3	$ 465.3
Less: Current maturities of long-term debt	17.1	17.2
Less: Unamortized debt issuance costs	4.3	4.2
Long-term debt	428.9	443.9
Revolving credit facility
Debt Instrument [Line Items]
Total long-term debt. gross	138.5	134.5
U.S. term loan
Debt Instrument [Line Items]
Total long-term debt. gross	228.1	240.6
Multi-currency term loans
Debt Instrument [Line Items]
Total long-term debt. gross	$ 83.7	$ 90.2

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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Amount of long-term debt classified as other, payable within one year or the operating cycle, if longer.

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