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GOVERNMENT GRANTS - Narrative (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023 | Dec. 31, 2023 | Feb. 28, 2022 | Nov. 30, 2020
Government Assistance [Line Items] |  |  |  |  |  |  |
Reimbursements received from the government |  |  | $ 96 | $ 1,050 |  |  |
Cost of sales (excluding depreciation, depletion and amortization) (including related party) | $ 57,266 | $ 22,217 | 134,323 | 69,137 |  |  |
Depreciation, depletion and amortization | (19,344) | (16,751) | (55,939) | (37,076) |  |  |
Technology Investment Agreement |  |  |  |  |  |  |
Government Assistance [Line Items] |  |  |  |  |  |  |
Technology investment agreement, stage II optimization contribution |  |  |  |  |  |  | $ 9,600
Reimbursements received from the government |  |  | 100 | 0 |  |  |
HREE Production Project Agreement |  |  |  |  |  |  |
Government Assistance [Line Items] |  |  |  |  |  |  |
Reimbursements received from the government |  |  | 0 | 1,100 |  |  |
HREE Production Project Agreement, stage II optimization contribution |  |  |  |  |  | $ 35,000 |
45 X Credit Government Grant |  |  |  |  |  |  |
Government Assistance [Line Items] |  |  |  |  |  |  |
Deferred government grant | 2,000 |  | 2,000 |  | $ 1,700 |  |
45 X Credit Government Grant | UNITED STATES |  |  |  |  |  |  |
Government Assistance [Line Items] |  |  |  |  |  |  |
Cash payments related to income taxes(1) | 19,400 |  |  |  |  |  |
45 X Credit Government Grant | Depreciation, depletion and amortization |  |  |  |  |  |  |
Government Assistance [Line Items] |  |  |  |  |  |  |
Benefits recognized pertaining to the 45X Credit | (500) | 0 | (1,400) | 0 |  |  |
45 X Credit Government Grant | Cost of sales (excluding depreciation, depletion and amortization) (including related party) |  |  |  |  |  |  |
Government Assistance [Line Items] |  |  |  |  |  |  |
Benefits recognized pertaining to the 45X Credit | $ (1,400) | $ 0 | $ (3,800) | $ 0 |  |  |

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