v3.26.1
Property, Plant, Equipment and Mine Development (Tables)
6 Months Ended
Jun. 30, 2026
Property, Plant, and Equipment [Abstract]  
Schedule of Property, Plant, Equipment and Mine Development
The composition of property, plant, equipment and mine development, net, as of June 30, 2026 and December 31, 2025 is set forth in the table below:
June 30, 2026December 31, 2025
(Dollars in millions)
Land and coal interests$2,689.7 $2,691.2 
Buildings and improvements771.6 758.8 
Machinery and equipment2,442.2 2,377.1 
Less: Accumulated depreciation, depletion and amortization(2,821.6)(2,673.8)
Property, plant, equipment and mine development, net$3,081.9 $3,153.3