DEBT / INTEREST EXPENSE - Schedule of Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Debt Instrument
Interest expense recognized on interest rate swap	$ 10,810	$ 0
Other	(90)	(9)
Interest expense, net	47,444	32,956
Senior Credit Facility
Debt Instrument
Amortization of discount and debt issuance costs	15,055	6,043
Interest expense	34,369	30,313
Senior Credit Facility \| Revolving Credit Facility
Debt Instrument
Interest expense (excluding amortization)	149	123
Senior Credit Facility \| FILO Term Loan \| Term Loan
Debt Instrument
Interest expense (excluding amortization)	6,826	6,751
Notes \| Convertible Senior Notes
Debt Instrument
Interest expense (excluding amortization)	596	707
Amortization of conversion feature	1,542	1,701
Amortization of discount and debt issuance costs	217	244
Interest expense	2,355	2,652
Tranche B-1 \| Senior Credit Facility \| Term Loan Facility
Debt Instrument
Interest expense (excluding amortization)	0	928
Tranche B-2 \| Senior Credit Facility \| Term Loan Facility
Debt Instrument
Interest expense (excluding amortization)	$ 12,339	$ 16,468

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Other Interest Income (Expense), Nonoperating, Net

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Amount of amortization expense attributable to debt discount (premium) and debt issuance costs.

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Gain (loss) incurred in hedging activities.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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Represents the portion of interest incurred in the period on debt arrangements that was charged against earnings, excluding amortization of debt discount (premium) and financing costs.

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The net amount of nonoperating interest income (expense).

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