LONG-TERM DEBT - Detail of Convertible Debt Carrying Amount (Details) - USD ($) $ in Thousands		Jun. 30, 2021	Dec. 31, 2020
Accounting Standards Update 2020-06 | Embedded Derivative Financial Instruments
Debt Instrument [Line Items]
Carrying amount of the equity component, net of issuance costs	[1]	$ 7,969	$ 7,969
Accounting Standards Update 2016-06 | Embedded Derivative Financial Instruments
Debt Instrument [Line Items]
Carrying amount of the equity component, net of issuance costs		37,276	37,276
Convertible debt
Debt Instrument [Line Items]
Principal		93,130	93,130
Unamortized issuance costs		(1,183)	(1,440)
Unamortized discount		(5,879)	(7,156)
Net carrying amount of the liability component	[2]	$ 86,068	$ 84,534

[1] Relates to the portion of the Notes accounted for under ASC 470-20 (defined below) and is included in the “Additional paid-in capital” line of the condensed consolidated balance sheets.

[2] Included in the “Long-term debt and finance lease obligations” line of the condensed consolidated balance sheets.