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DEBT OBLIGATIONS - Offtake Advances (Details) - USD ($) $ in Thousands	1 Months Ended				12 Months Ended
	Mar. 31, 2022	Jan. 31, 2021	Aug. 31, 2020	Jun. 30, 2020	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Principal payments on debt obligations and finance leases					$ 5,834	$ 2,435	$ 20,180
Shenghe | Affiliated Entity
Debt Instrument [Line Items]
Principal payments on debt obligations and finance leases	$ 2,900
Shenghe
Debt Instrument [Line Items]
Rebate income		$ 2,200	$ 9,700
Gross profit, higher than estimate							400
Long-term debt to related party
Debt Instrument [Line Items]
Debt discount					0	517
Current					0	16,082
Offtake Advances | Long-term debt to related party
Debt Instrument [Line Items]
Required payments, percent of net profits from sales of assets				100.00%
Required payments, percent of net income				100.00%
Reduction in debt as a result of sales					14,200	52,800	12,000
Reduction due to sales to other parties					200	200
Outstanding balance, gross					$ 0	16,599
Reduction in debt principal due to change in price estimates						2,200	10,100
Reduction in debt discount due to change in price estimates						$ 200	$ 800
Offtake Advances | Long-term debt to related party | Minimum
Debt Instrument [Line Items]
Effective interest rate					4.41%
Offtake Advances | Long-term debt to related party | Maximum
Debt Instrument [Line Items]
Effective interest rate					24.75%
Offtake Advances | Second Offtake Advance
Debt Instrument [Line Items]
Advance funded				$ 35,500

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