DEBT - Schedule of Debt and Capital Leases (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Finance leases	$ 82.8	$ 67.3
Debt issuance costs	(7.8)	(7.2)
Total debt	789.9	687.3
Less: current maturities	(27.3)	(32.5)
Long-term debt, net of current maturities	762.6	654.8
Unsecured notes \| 2024 Notes
Debt Instrument [Line Items]
Long-term debt	$ 606.5	$ 606.8
Effective interest rate (as a percent)	6.56%	6.56%
Asset based revolving credit facility
Debt Instrument [Line Items]
Long-term debt	$ 90.3	$ 0.0
Promissory notes
Debt Instrument [Line Items]
Long-term debt	$ 18.1	$ 20.4

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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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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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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Present value of lessee's discounted obligation for lease payments from finance lease.

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Amount of long-term debt and lease obligation, classified as noncurrent.

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Amount of long-term debt and lease obligation, classified as current.

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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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