Pneumoconiosis ("Black Lung") Obligations (Details) - USD ($) $ / shares in Units, $ in Thousands |
12 Months Ended | |||||||
|---|---|---|---|---|---|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
Jun. 01, 2024 |
May 31, 2024 |
Jul. 12, 2022 |
May 31, 2020 |
Feb. 21, 2020 |
Apr. 01, 2016 |
|
| Self Insurance Reserve Disclosure [Abstract] | ||||||||
| Deductible amount per black lung claim | $ 2,000 | $ 1,000 | $ 500 | |||||
| Collateral securities | $ 28,000 | $ 39,800 | $ 17,000 | |||||
| Surety Bonds | $ 18,600 | $ 18,600 | ||||||
| Short-term investments | 9,900 | 9,500 | ||||||
| Black lung trust | 900 | 1,400 | ||||||
| Estimated total black lung liabilities | 36,100 | 36,700 | ||||||
| Black lung obligations, current | 2,100 | 2,200 | ||||||
| Black lung obligations, noncurrent | 34,036 | 34,467 | ||||||
| Self insurance expense (income) | $ (1,300) | $ 7,300 | ||||||
| Self insurance reserve, adjustment to earnings (in USD per share) | $ 0.02 | $ 0.14 | ||||||