Inventories

12 Months Ended

Dec. 31, 2020

Inventory Disclosure [Abstract]

Inventories

Inventories

    The major components of inventories were as follows:

	December 31,
	2020		2019
Petroleum products	$	5,840	$	2,721
Crude oil	37,661		5,271
Caustic soda	5,167		5,965
NaHS	9,101		10,845
Raw materials - Alkali Operations	7,120		6,238
Work-in-process - Alkali Operations	9,355		8,579
Finished goods, net - Alkali Operations	13,002		14,168
Materials and supplies, net - Alkali Operations	12,631		11,350
Total	$	99,877	$	65,137

    Inventories are valued at the lower of cost or net realizable value. The net realizable value of inventories were recorded below cost by $5.0 million as of December 31, 2020, therefore we reduced the value of inventory in our Consolidated Financial Statements by this amount. There was no such adjustment as of December 31, 2019.

    Materials and supplies include chemicals, maintenance supplies, and spare parts which will be consumed in the mining of trona ore and production of soda ash processes.