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PROPERTY, PLANT AND EQUIPMENT (Tables)
12 Months Ended
Dec. 31, 2020
PROPERTY, PLANT AND EQUIPMENT  
Schedule of property, plant and equipment

    

December 31,

 

2020

    

2019

(in thousands)

Mining equipment and processing facilities

$

1,896,324

$

1,937,642

Land and coal mineral rights

 

454,310

 

453,237

Oil & gas mineral interests (1)

616,904

618,282

Buildings, office equipment and improvements

 

279,938

 

304,111

Construction and mine development in progress

 

25,799

 

86,876

Mine development costs

 

280,815

 

283,860

Property, plant and equipment, at cost

 

3,554,090

 

3,684,008

Less accumulated depreciation, depletion and amortization

 

(1,753,845)

 

(1,675,022)

Total property, plant and equipment, net

$

1,800,245

$

2,008,986

(1)Oil & gas mineral interests acquired in the AllDale and Wing Acquisitions. See Note 3 – Acquisitions for more information.