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Convertible Debt, Royalty and Production Payment Arrangements - Additional Information (Details) $ / shares in Units, $ in Thousands, shares in Millions		1 Months Ended
	Apr. 01, 2025 USD ($) Tonnes $ / shares	Oct. 31, 2025 USD ($) shares	Jun. 30, 2026 USD ($)	Dec. 31, 2025 USD ($)	Mar. 31, 2025 USD ($)
Gain Contingencies [Line Items]
Obligated to gross revenue royalty	20.00%
Orion Resource Partners LP (Orion) [Member]
Gain Contingencies [Line Items]
Aggregate principal amount	$ 195,000
Delayed Draw Notes [Member] \| Orion Resource Partners LP (Orion) [Member]
Gain Contingencies [Line Items]
Additional commitment amount	$ 30,000
Convertible Debt [Member]
Gain Contingencies [Line Items]
Aggregate principal amount			$ 116,000	$ 110,478	$ 195,000
Initial conversion price \| $ / shares	$ 3.78
Debt conversion amount		$ 97,500
Shares issued for debt conversion \| shares		25.8
Interest rate on convertible debt	9.875%
Maturity date	Apr. 01, 2030
Effective interest			26.40%
PPA [Member]
Gain Contingencies [Line Items]
Effective interest			27.00%
Fixed and variable payments recieved \| Tonnes	41,500
Phase 1 of Thacker Pass [Member] \| Orion Resource Partners LP (Orion) [Member]
Gain Contingencies [Line Items]
Investments	$ 250,000
Thacker Pass [Member] \| Orion Resource Partners LP (Orion) [Member]
Gain Contingencies [Line Items]
Amount paid for exchange	$ 25,000
Thacker Pass [Member]
Gain Contingencies [Line Items]
Obligated to gross revenue royalty	8.00%
Mineral claims	$ 22,000
Rate of royalty	4.00%
Option at any time to reduce rate of royalty	1.75%