XML 199 R69.htm IDEA: XBRL DOCUMENT v3.22.0.1
INVENTORIES (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
INVENTORIES      
Coal $ 24,845 $ 19,756  
Supplies (net of reserve for obsolescence of $5,554 and $5,547, respectively) 35,457 36,651  
Total inventories, net 60,302 56,407  
Reserve for obsolescence 5,554 5,547  
Reduce inventory carrying value to market $ 70 $ 3,245 $ 4,895