DEBT OBLIGATIONS - Schedule of Long-Term Debt (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Total debt obligations	$ 499,369	$ 495,479
Less: current portion of long-term debt	(7,866)	(4,007)
Less: unamortized debt discounts and deferred financing costs	(8,184)	(5,894)
Long-term debt, net	$ 483,319	$ 485,578
Syndicate of Lenders \| Line of Credit
Debt Instrument [Line Items]
Interest rate during period	8.11%	6.71%
Syndicate of Lenders \| Line of Credit \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	6.50%	5.00%
Syndicate of Lenders \| Line of Credit \| Revolving Credit Facility
Debt Instrument [Line Items]
Total debt obligations	$ 15,000
Syndicate of Lenders \| Line of Credit \| Term Loan
Debt Instrument [Line Items]
Total debt obligations	$ 387,836
Goldman Sachs Specialty Lending Group \| Line of Credit
Debt Instrument [Line Items]
Basis spread on variable rate	5.00%
Interest rate during period	12.50%	10.50%
Goldman Sachs Specialty Lending Group \| Line of Credit \| Payment-in-Kind Interest Rate
Debt Instrument [Line Items]
Basis spread on variable rate	5.00%	5.00%
Goldman Sachs Specialty Lending Group \| Line of Credit \| Term Loan
Debt Instrument [Line Items]
Total debt obligations	$ 96,533
Senior Term Loan, Maturing January 3, 2023 \| Senior Notes
Debt Instrument [Line Items]
Total debt obligations	387,800
Senior Term Loan, Maturing January 3, 2023 \| Syndicate of Lenders \| Senior Notes
Debt Instrument [Line Items]
Total debt obligations	387,836	$ 388,837
Senior Term Loan, Maturing January 3, 2023 \| Syndicate of Lenders \| Line of Credit \| Revolving Credit Facility
Debt Instrument [Line Items]
Total debt obligations	15,000	11,500
Senior Term Loan, Maturing January 3, 2023 \| Syndicate of Lenders \| Line of Credit \| Letter of Credit
Debt Instrument [Line Items]
Total debt obligations	25,000	25,000
Subordinated Term Loan, Maturing July 3, 2023 \| Goldman Sachs Specialty Lending Group \| Subordinated Debt
Debt Instrument [Line Items]
Total debt obligations	$ 96,533	$ 95,142

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount, after accumulated amortization, of debt discount.

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The effective interest rate at the end of the reporting period.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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