XML 44 R31.htm IDEA: XBRL DOCUMENT v3.21.2
Inventories (Tables)
9 Months Ended
Sep. 30, 2021
Inventory Disclosure [Abstract]  
Schedule of Inventories
Inventories as of September 30, 2021 and December 31, 2020 consisted of the following:
September 30, 2021December 31, 2020
 (Dollars in millions)
Materials and supplies$98.3 $102.6 
Raw coal53.5 70.5 
Saleable coal72.7 88.5 
Total$224.5 $261.6