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 discount.

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LONG-TERM DEBT / INTEREST EXPENSE - Schedule of Total Debt Principal Maturities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Feb. 28, 2018
Debt Instrument [Line Items]
2020	$ 185,006
2021	422,553
2022	275,000
Total	882,559
Notes (net of $3.9 million and $11.5 million conversion feature and $0.5 million and $1.6 million discount)
Debt Instrument [Line Items]
Debt instrument, unamortized discount	3,900	$ 11,500
Term Loan
Debt Instrument [Line Items]
Debt instrument, unamortized discount	0		$ 30,200
Notes (net of $3.9 million and $11.5 million conversion feature and $0.5 million and $1.6 million discount) \| Notes (net of $3.9 million and $11.5 million conversion feature and $0.5 million and $1.6 million discount)
Debt Instrument [Line Items]
2020	159,097
2021	0
2022	0
Total	159,097
Debt instrument, unamortized discount	3,898	11,489
Original issuance discount	524	1,572
Term Loan \| FILO Term Loan \| FILO Asset-based Term Loan Facility
Debt Instrument [Line Items]
2020	0
2021	0
2022	275,000
Total	275,000
Debt instrument, unamortized discount	8,200	10,900
Tranche B-2 \| Term Loan \| Amended Term Loan Facility Due March 2021
Debt Instrument [Line Items]
2020	25,909
2021	422,553
2022	0
Total	448,462
Debt instrument, unamortized discount	$ 7,000	$ 17,500