CONVERTIBLE NOTES AND CREDIT FACILITY - Interest Expense (Details) - Convertible Debt - Senior Convertible Note - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Debt Instrument [Line Items]
Interest expense related to contractual coupon interest	$ 809	$ 809
Interest expense related to amortization of the debt discount	107	102
Interest expense, debt	$ 916	$ 911

Amount of the cost of borrowed funds accounted for as interest expense for debt.

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Name:	us-gaap_InterestExpenseDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration