FAIR VALUE MEASUREMENTS AND FINANCIAL INSTRUMENTS - Fair Value Measurements, Recurring and Nonrecurring (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Assets:
Cash and cash equivalents	$ 79,952	$ 98,132
Restricted cash	3,935	4,017
Short-term receivable	3,688	3,643
Level 1 \| Fair Value, Measurements, Recurring
Assets:
Cash and cash equivalents	79,952	98,132
Restricted cash	3,935	4,017
Short-term receivable	0	0
Level 2 \| Fair Value, Measurements, Recurring
Assets:
Cash and cash equivalents	0	0
Restricted cash	0	0
Short-term receivable	0	0
Level 3 \| Fair Value, Measurements, Recurring
Assets:
Cash and cash equivalents	0	0
Restricted cash	0	0
Short-term receivable	3,688	3,643
Senior secured term loan
Liabilities:
Convertible debt payable to related parties	247,204	247,204
Senior secured term loan \| Level 1 \| Fair Value, Measurements, Recurring
Liabilities:
Convertible debt payable to related parties	0	0
Senior secured term loan \| Level 2 \| Fair Value, Measurements, Recurring
Liabilities:
Convertible debt payable to related parties	220,012	224,956
Senior secured term loan \| Level 3 \| Fair Value, Measurements, Recurring
Liabilities:
Convertible debt payable to related parties	$ 0	$ 0

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Amount of asset recognized arising from contingent consideration in a business combination, expected to be realized within one year or the normal operating cycle, if longer.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as noncurrent. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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