The following summarizes our inventory, recorded at the lower of weighted average cost or estimated net realizable value, as of March 31, 2017, and December 31, 2016 (in thousands):



	March 31, 2017		December 31, 2016
Finished goods product inventory	$	52,396	$	52,571
In-process mineral inventory	16,377		22,126
Total product inventory	68,773		74,697
Current parts inventory, net	17,421		19,658
Total current inventory, net	86,194		94,355
Long-term parts inventory, net	23,731		21,037
Total inventory, net	$	109,925	$	115,392