| Line Item | Jun 30, 2026 | Mar 31, 2026 | Dec 31, 2025 | Sep 30, 2025 | Jun 30, 2025 | Mar 31, 2025 | Dec 31, 2024 | Sep 30, 2024 | Jun 30, 2024 | Mar 31, 2024 | Dec 31, 2023 | Sep 30, 2023 | Jun 30, 2023 | Mar 31, 2023 | Dec 31, 2022 | Sep 30, 2022 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Operating expenses | ||||||||||||||||
| Exploration expenditures | — | |||||||||||||||
| Total operating expenses | ||||||||||||||||
| Change in fair value of earnout shares liability | ||||||||||||||||
| Change in fair value of warrant liabilities | ||||||||||||||||
| Change in fair value of convertible notes | — | |||||||||||||||
| Interest expense | — | |||||||||||||||
| Interest income | ||||||||||||||||
| Loss before income taxes | ||||||||||||||||
| Income tax benefit | — | |||||||||||||||
| Net loss | — | |||||||||||||||
| Less: Net loss attributable to redeemable noncontrolling interest | — | |||||||||||||||
| Net loss attributable to the Company | — | |||||||||||||||
| Less: Comprehensive loss attributable to redeemable noncontrolling interest | — | — | — | |||||||||||||
| Comprehensive loss attributable to the Company | — | — | — | |||||||||||||
| Loss per common share, basic | — | — | ||||||||||||||
| Loss per common share, diluted | — | — |