RELATED PARTY TRANSACTIONS - Narrative (Details) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
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| Related Party Transaction [Line Items] | ||||
| Revenue (including related party) | $ 147,655 | $ 53,553 | $ 346,794 | $ 171,756 |
| Cost of sales (excluding depreciation, depletion and amortization) (including related party) | $ 85,628 | 48,477 | $ 232,165 | 147,739 |
| Purchases from related party | 3,600 | 19,700 | ||
| Related party | ||||
| Related Party Transaction [Line Items] | ||||
| Cost of sales (excluding depreciation, depletion and amortization) (including related party) | 0 | 31,400 | ||
| Related party | Rare Earth Concentrate | ||||
| Related Party Transaction [Line Items] | ||||
| Revenue (including related party) | 0 | 42,000 | ||
| Related party | NdPr Oxide And Metal | ||||
| Related Party Transaction [Line Items] | ||||
| Revenue (including related party) | $ 0 | $ 9,300 | ||
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- Definition Cost of product sold and service rendered, excluding depreciation, depletion, and amortization. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party. No definition available.
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- Definition Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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