LOANS PAYABLE - Summary (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
LOAN PAYABLE
Loan payable	$ 30,000	$ 30,000
End of term fee	975	975
Loan payable, gross	30,975	30,975
Less: unamortized debt issuance costs	(386)	(1,080)
Loan payable	30,589	29,895
Less: principal payments	(14,590)
Total loan payable	15,999	29,895
Less: Current portion	$ (15,999)	(22,179)
Loan payable non-current		$ 7,716

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Long term debt excluding principal payments

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Refers to the amount of long term debt principal payments.

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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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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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Amount of long-term debt classified as other.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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