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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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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI https://asc.fasb.org/extlink&oid=123466204&loc=SL6031897-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878 + Details
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