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Inventories (Tables)
3 Months Ended
Mar. 31, 2021
Inventories  
Inventories

    

March 31, 

    

December 31, 

 

2021

 

2020

(In thousands)

Coal

$

74,344

$

49,436

Repair parts and supplies

 

80,051

 

76,572

$

154,395

$

126,008