v3.26.1
Fair Values of Financial Instruments - Summary of Carrying Amount and Fair Values (Details) - USD ($)
$ in Thousands
Jun. 30, 2026
Dec. 31, 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Royalty obligation [1] $ 21,386 $ 21,160
Production payment obligation, Carrying Value [2] 34,248 29,684
Convertible Debt host , Carrying Value [3] 65,341 57,649
DOE Loan, Carrying Value [4] 988,018 350,987
Total, Carrying Value 1,108,993 459,480
Royalty obligation [1] 15,527 13,699
Production payment obligation, Fair Value [2] 33,320 32,717
Convertible Debt, Fair Value [3] 69,346 62,367
DOE Loan, Fair Value [4] 735,144 301,630
Total, Fair Value $ 853,337 $ 410,413
[1] The estimated fair value involved Level 3 inputs and was determined using a discounted cash flow with a discount rate of 26.4% at June 30, 2026 (December 31, 2025 - 26.1%).
[2] The estimated fair value involved Level 3 inputs and was determined using a discounted cash flow with a discount rate of 27.0% at June 30, 2026 (December 31, 2025 - 26.8%).
[3] The estimated fair value involved Level 3 inputs and was determined using a discount rate of 26.4% at June 30, 2026 (December 31, 2025 - 26.1%).
[4] The estimated fair value involved Level 3 inputs and was determined using a discount rate of 9.9% at June 30, 2026 (December 31, 2025 - 8.0%).