(2)Inventory

Inventories are stated at the lower of cost or market. Cost is determined using the first-in, first-out or weighted-average cost methods for finished goods and work-in-process. Supplies and consumables consist principally of products used in our services provided to customers. The components of the inventory balances are as follows (in thousands):



	March 31, 2016		December 31, 2015
Finished goods	$	71,377	$	71,951
Raw materials		17,387		23,418
Work-in-process		6,276		18,203
Supplies and consumables		36,271		35,189
Total	$	131,311	$	148,761