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LONG-LIVED ASSET IMPAIRMENTS (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2025 | Sep. 30, 2025 | Dec. 31, 2024
LONG-LIVED ASSET IMPAIRMENTS |  |  |
Impairment charge |  |  | $ 215,100
Asset impairment charges | $ 0 | $ 0 |
Coal Operations | Operating Segment |  |  |
LONG-LIVED ASSET IMPAIRMENTS |  |  |
Impairment charge |  |  | $ 215,100

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