DEBT - Summary of Long-term Debt (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021	May 20, 2020
Debt Instrument [Line Items]
Gross, long-term debt	$ 73,521	$ 73,493
Less: current portion of long-term debt	(12,271)	(12,174)
Net, long-term debt	61,250	61,319
Royalty rights obligation
Debt Instrument [Line Items]
Gross, long-term debt	$ 2,800	2,700
Senior Notes \| Senior Secured Notes Due 2024
Debt Instrument [Line Items]
Interest rate	13.00%		13.00%
Gross, long-term debt	$ 70,750	70,750
Less: current portion of long-term debt	(9,500)	(9,500)
Net, long-term debt	61,300	61,300
Senior Notes \| Royalty rights obligation
Debt Instrument [Line Items]
Gross, long-term debt	$ 2,771	$ 2,743

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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Contractual interest rate for funds borrowed, under the debt agreement.

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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 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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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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