DEBT - Schedule of Future Minimum Payments Under Term Loan Agreement (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Debt Disclosure [Abstract]
Remainder of 2021	$ 796
2022	5,858
2023	19,187
2024	18,338
Total	44,179
Less: amount representing interest	(6,887)
Less: unamortized debt discount and issuance costs	(836)
Less: unaccrued end of term charge	(1,787)
Noncurrent portion of debt	$ 34,669	$ 24,042

Debt instrument unaccrued end of term charge.

No definition available.

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Aggregate value of term loan, including accrued interest payable and end of term charge.

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Amount, after accumulated amortization, of debt discount.

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Amount of interest payable on debt, including, but not limited to, trade payables.

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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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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