Mineral Properties, Plant and Equipment, Net - Schedule of Mineral Properties, Plant and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Property, Plant and Equipment [Line Items]
Total mineral properties, plant and equipment	$ 480,556	$ 402,659
Accumulated depreciation	(4,778)	(3,711)
Total mineral properties, plant and equipment, net	475,778	398,948
Thacker Pass [Member]
Property, Plant and Equipment [Line Items]
Total mineral properties, plant and equipment	457,146	378,957
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Total mineral properties, plant and equipment	2,681	2,638
Finance Lease Right of Use Assets [Member]
Property, Plant and Equipment [Line Items]
Total mineral properties, plant and equipment	19,948	19,948
Other Mineral Properties Plant and Equipment [Member]
Property, Plant and Equipment [Line Items]
Total mineral properties, plant and equipment	$ 781	$ 1,116