LONG-TERM OBLIGATIONS - Schedule of Long-Term Debt (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Principal amount	$ 452.8	$ 217.7
Deferred debt issuance costs	(4.8)	(2.7)
Long-term obligations, including current portion	448.0	215.0
Current portion of long-term obligations	(13.2)	(10.5)
Long-term obligations, less current portion	434.8	204.5
Term Loan [Member] \| Four Hundred Fifty Million Term Loan Facility
Debt Instrument [Line Items]
Principal amount	450.0	164.1
Revolving Credit Facility [Member] \| Five Hundred Fifty Million Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Principal amount	0.0	51.0
Promissory Notes [Member]
Debt Instrument [Line Items]
Principal amount	0.8	0.0
Finance leases [Member]
Debt Instrument [Line Items]
Principal amount	$ 2.0	$ 2.6

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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