Mineral Rights and Properties, Net - Summary of Mineral Rights and Properties, Net (Parenthetical) (Detail) - USD ($) $ in Thousands |
Jun. 30, 2026 |
Jun. 30, 2025 |
|---|---|---|
| Asset Retirement Cost [Member] | ||
| Mineral Properties Net [Line Items] | ||
| Asset retirement cost, accumulated amortization | $ 201 | $ 66 |