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Inventories
3 Months Ended
Mar. 31, 2017
Inventory Disclosure [Abstract]  
Inventories
INVENTORIES:

Inventory components consist of the following:
 
March 31,
2017
 
December 31,
2016
Coal
$
12,626

 
$
7,800

Supplies
56,992

 
57,661

Total Inventories
$
69,618

 
$
65,461



Inventories are stated at the lower of cost or net realizable value. The cost of coal inventories is determined by the first-in, first-out (FIFO) method. Coal inventory costs include labor, supplies, equipment costs, operating overhead, depreciation, depletion and amortization, and other related costs. The cost of supplies inventory is determined by the average cost method and includes operating and maintenance supplies to be used in the Company's E&P and coal operations.