INVENTORY AND LONG-TERM PARTS INVENTORY (Tables)

12 Months Ended

Dec. 31, 2019

Inventory Disclosure [Abstract]

Summary of Inventory

The following summarizes our inventory, recorded at the lower of weighted average cost or estimated net realizable value as of December 31, 2019, and 2018, respectively (in thousands):

	December 31,
	2019		2018
Finished goods product inventory	$	55,585	$	48,370
In-process mineral inventory	25,591		24,325
Total product inventory	81,176		72,695
Current parts inventory, net	13,044		9,351
Total current inventory, net	94,220		82,046
Long-term parts inventory, net	27,569		30,031
Total inventory, net	$	121,789	$	112,077