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DEBT OBLIGATIONS - Current and Non-current Portions of Long-term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Less: Unamortized debt issuance costs	$ (11,556)	$ (15,073)
Long-term debt, net of current portion	678,444	674,927
Long-term debt to related party
Debt Instrument [Line Items]
Less: Unamortized debt discount	0	(517)
Net carrying amount	0	16,082
Less: Current installments of long-term debt to related party	0	(16,082)
Long-term debt, net of current portion	0	0
Convertible Notes | Convertible Notes Due 2026
Debt Instrument [Line Items]
Long-term debt to related parties, gross	690,000	690,000
Net carrying amount	690,000
Offtake Advances | Long-term debt to related party
Debt Instrument [Line Items]
Long-term debt to related parties, gross	$ 0	$ 16,599

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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