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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 3
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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	Sep. 30, 2020	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	$ 22.0	$ 145.2
Long-term Debt, Maturities, Repayments of Principal in Year Three	22.0	500.0
Long-term Debt, Maturities, Repayments of Principal in Year Four	22.0	2,070.0
Long-term Debt, Maturities, Repayments of Principal in Year Five	$ 22.0	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