Inventories

3 Months Ended

Mar. 31, 2021

Costs included in inventories are raw materials, labor, supplies and allocable depreciation and overhead. Raw material inventories are valued on an average cost basis. Other inventory cost elements are valued at cost, using the first-in, first-out method. The Company writes down the inventories for estimated obsolescence, and to lower of cost or net realizable value based upon assumptions about future demand and market conditions. If actual demand or market conditions are less favorable than those projected by the Company, additional inventory write-downs may be required. Once established, the original cost of the inventory less the related write-down represents the new cost basis of such inventories.

As of March 31, 2021 and December 31, 2020, Inventories consisted of the following:


(in thousands)	March 31, 2021		December 31, 2020
Raw materials	$	60,391	$	57,789
Work in process	41,593		40,416
Finished goods	15,038		12,273
Total inventories	$	117,022	$	110,478