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During Period, Value, Conversion of Convertible Securities Preferred stock, authorized (in shares) Preferred Stock, Shares Authorized Unusual Risk or Uncertainty [Line Items] Unusual Risk or Uncertainty [Line Items] Property, Plant, and Equipment [Table] Property, Plant, and Equipment [Table] Grants Receivable, Noncurrent Grants Receivable, Noncurrent Preferred stock, undesignated ($0.0001 par value, 49,600,000 shares authorized as of June 30, 2026, and December 31, 2025, respectively, zero issued and outstanding in either period) Preferred Stock, Value, Issued Adjustment to Compensation: Adjustment to Compensation [Axis] Percentage of difference between Benchmark Price and price floor to be paid Price Protection Agreement, Percentage of Difference between Benchmark Price and Price Floor to be Paid Price Protection Agreement, Percentage of Difference between Benchmark Price and Price Floor to be Paid Class of Stock [Domain] Class of Stock [Domain] Rule 10b5-1 Arrangement Terminated 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Category Entity Filer Category Credit Agreement, Covenant, Total Leverage Ratio, Stepped Up, Maximum Debt Instrument, Total Leverage Ratio, Stepped Up, Following Covenant Trigger Event, Maximum Debt Instrument, Total Leverage Ratio, Stepped Up, Following Covenant Trigger Event, Maximum NdPr Oxide And Metal NdPr Oxide And Metal [Member] NdPr Oxide And Metal Name Trading Arrangement, Individual Name Cash and cash equivalents Cash and Cash Equivalent Term to maturity Measurement Input, Expected Term [Member] Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration] Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration] Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Company Selected Measure Amount Company Selected Measure Amount Initial start-up costs Initial Start-up Costs Initial Start-up Costs Investments, Debt and Equity Securities [Abstract] Depreciation, depletion and amortization 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Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block]