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RELATIONSHIP AND AGREEMENTS WITH SHENGHE - Framework Agreement and Restructured Commercial Arrangements (Details) - USD ($) $ in Thousands |  |  |  | 1 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
Jun. 05, 2020 | Jun. 02, 2020 | Jun. 20, 2017 | Mar. 31, 2022 | May 31, 2017 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Principal payments on debt obligations and finance leases |  |  |  |  |  | $ 5,834 | $ 2,435 | $ 20,180
Affiliated Entity | Shenghe |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Principal payments on debt obligations and finance leases |  |  |  | $ 2,900 |  |  |  |
Original Offtake Agreement, Second Additional Advance | Affiliated Entity | Shenghe |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Advances | $ 35,500 |  |  |  |  |  |  |
Initial Prepayment Amount | Affiliated Entity |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Advances |  |  |  |  | $ 50,000 |  |  |
Increase in advances |  |  | $ 30,000 |  |  |  |  |
Initial Prepayment Amount | Affiliated Entity | Shenghe |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Increase in advances | $ 30,000 |  |  |  |  |  |  |
MPMO | A&R Offtake Agreement | Affiliated Entity | Shenghe Warrant | Shenghe |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Number of preferred units convertible from warrant exercise (in shares) |  | 89.88 |  |  |  |  |  |
Percentage of equity on a diluted basis after warrant exercise |  | 7.50% |  |  |  |  |  |

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- Definition Number of securities into which each warrant or right may be converted. For example, but not limited to, each warrant may be converted into two shares. + References No definition available. + Details
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- Definition Amount of cash outflow for debt, mandatory redeemable security, and principal payment for finance lease obligation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (a),(b) -URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3291-108585 + Details
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