Coal Workers' Pneumoconiosis and Workers' Compensation - Narrative (Details) $ in Thousands	Dec. 31, 2025 USD ($)
Workers Compensation, Insured Plan
Defined Benefit Plan Disclosure [Line Items]
Workers' compensation obligation	$ 40,971
Workers Compensation, Insured Plan, Reimbursable
Defined Benefit Plan Disclosure [Line Items]
Workers' compensation obligation	$ 4,480

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.

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+ Details