Components of Coal Workers' Pneumoconiosis (CWP) and Workers' Compensation Net Periodic Benefit Costs (Details) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
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| CWP | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Service Cost | $ 1,690 | $ 2,003 | $ 5,071 | $ 5,809 |
| Interest Cost | 3,382 | 3,687 | 10,145 | 10,776 |
| Recognized Net Actuarial Loss (Gain) | 317 | 42 | 952 | 127 |
| State Administrative Fees and Insurance Bond Premiums | 0 | 0 | 0 | 0 |
| Net Periodic Benefit Cost | 5,389 | 5,732 | 16,168 | 16,712 |
| Workers' Compensation | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Service Cost | 3,196 | 1,728 | 9,586 | 5,184 |
| Interest Cost | 502 | 555 | 1,504 | 1,665 |
| Recognized Net Actuarial Loss (Gain) | (357) | (460) | (1,069) | (1,380) |
| State Administrative Fees and Insurance Bond Premiums | 779 | 672 | 2,340 | 1,802 |
| Net Periodic Benefit Cost | 4,120 | 2,495 | 12,361 | 7,271 |
| Insured Workers’ Compensation Fees and Assessments | 519 | 1,601 | 1,556 | 4,581 |
| Total Workers’ Compensation Expense | $ 4,639 | $ 4,096 | $ 13,917 | $ 11,852 |
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- Definition Defined Benefit Plan, Workers Compensation Expense No definition available.
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- Definition Defined Benefit Plan, Workers Compensation Expense Insured Portion No definition available.
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- Definition State Administrative Fees and Insurance Bond Premiums No definition available.
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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of cost recognized for passage of time related to defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of net periodic benefit cost (credit) for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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