Mineral Properties, Plant and Equipment, Net - Schedule of Mineral Properties, Plant and Equipment, Net (Details) - USD ($) $ in Thousands |
Jun. 30, 2026 |
Dec. 31, 2025 |
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|---|---|---|---|---|
| Property, Plant and Equipment [Line Items] | ||||
| Total mineral properties, plant and equipment | $ 2,148,355 | $ 1,358,227 | ||
| Accumulated depreciation | (57,599) | (14,223) | ||
| Total mineral properties, plant and equipment, net | 2,090,756 | 1,344,004 | ||
| Thacker Pass - construction in progress [Member] | ||||
| Property, Plant and Equipment [Line Items] | ||||
| Total mineral properties, plant and equipment | [1] | 1,925,885 | 1,235,620 | |
| Thacker Pass - property, plant and equipment [Member] | ||||
| Property, Plant and Equipment [Line Items] | ||||
| Total mineral properties, plant and equipment | 197,111 | 98,740 | ||
| Machinery and Equipment [Member] | ||||
| Property, Plant and Equipment [Line Items] | ||||
| Total mineral properties, plant and equipment | 4,044 | 3,955 | ||
| Finance Lease Right of Use Assets [Member] | ||||
| Property, Plant and Equipment [Line Items] | ||||
| Total mineral properties, plant and equipment | $ 21,315 | $ 19,912 | ||
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