DEBT - Schedule of Debt Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Less: current portion	$ (11,248)	$ (35,314)
Loans Payable
Debt Instrument [Line Items]
Loan payable to MGG	11,248	35,500
Unamortized original issue discount	0	(1,418)
Unamortized debt issuance cost	0	(18)
Carrying value of Loan	11,248	34,064
Exit fee payable in relation to Loan	0	1,250
Total long-term debt	0	35,314
Less: current portion	0	(35,314)
Long-term debt, less current portion and net of debt issuance cost	$ 0	$ 0

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 the fee that accompanies borrowing money under the debt instrument.

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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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