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 of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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DEBT - Contractual maturities of debt obligation (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Feb. 09, 2017
Maturities of Long-term Debt [Abstract]
Long-term Debt, Maturities, Repayments of Principal in Year Two	$ 145.2
Long-term Debt, Maturities, Repayments of Principal in Year Three	500.0
Long-term Debt, Maturities, Repayments of Principal in Year Four	2,070.0
Long-term Debt, Maturities, Repayments of Principal in Year Five	870.0
Long-term Debt, Gross	3,585.2
Term Loan due 2023
Maturities of Long-term Debt [Abstract]
Long-term Debt, Maturities, Repayments of Principal in Year Four	2,070.0
Long-term Debt, Gross	2,070.0	$ 2,070.0	$ 2,245.0
9.250% Senior notes due 2024
Maturities of Long-term Debt [Abstract]
Long-term Debt, Maturities, Repayments of Principal in Year Five	750.0
Long-term Debt, Gross	750.0	750.0
12.00%/13.00% PIK notes due 2022
Maturities of Long-term Debt [Abstract]
Long-term Debt, Maturities, Repayments of Principal in Year Three	500.0
Long-term Debt, Gross	500.0	500.0
ABL Revolving Credit Facility
Maturities of Long-term Debt [Abstract]
Long-term Debt, Maturities, Repayments of Principal in Year Two	145.2
Long-term Debt, Gross	145.2	$ 245.1
10.00% notes due 2024
Maturities of Long-term Debt [Abstract]
Long-term Debt, Maturities, Repayments of Principal in Year Five	120.0
Long-term Debt, Gross	$ 120.0