v3.25.4

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 |  |  |  |  |  |

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- Definition Assets Held-In-Trust, Self Insurance Reserve, Noncurrent + References No definition available. + Details
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- Definition Held-To-Maturity Securities Held As Collateral + References No definition available. + Details
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- Definition Held-To-Maturity of Short term Investments Held As Collateral + References No definition available. + Details
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- Definition Held-To-Maturity of Surety Bonds + References No definition available. + Details
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- Definition Self Insurance Reserve, Adjustment Expense (Income) + References No definition available. + Details
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- Definition Self Insurance Reserve, Adjustment To Earnings, Per Share + References No definition available. + Details
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- Definition Self Insurance Reserve, Deductible Amount Per Claim + References No definition available. + Details
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- Definition Self Insurance Reserve Disclosure [Abstract] + References No definition available. + Details
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- Definition Carrying amount (including both current and noncurrent portions) of accrued known and estimated losses incurred as of the balance sheet date for which no insurance coverage exists, and for which a claim has been made or is probable of being asserted, typically arising from workmen's compensation-type of incidents and personal injury to nonemployees from accidents on the entity's property. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(24)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 + Details
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- Definition Carrying amount of accrued known and estimated losses incurred as of the balance sheet date for which no insurance coverage exists, and for which a claim has been made or is probable of being asserted, typically arising from workmen's compensation-type of incidents and personal injury to nonemployees from accidents on the entity's property that are expected to be paid within one year (or the normal operating cycle, if longer). + References No definition available. + Details
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- Definition Carrying amount of accrued known and estimated losses incurred as of the balance sheet date for which no insurance coverage exists, and for which a claim has been made or is probable of being asserted, typically arising from workmen's compensation-type of incidents and personal injury to nonemployees from accidents on the entity's property that are expected to be paid after one year (or the normal operating cycle, if longer). + References No definition available. + Details
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