Inventories

12 Months Ended

Dec. 31, 2021

Inventory Disclosure [Abstract]

Inventories

Inventories

The major components of inventories were as follows:

	December 31,
	2021		2020
Petroleum products	$	998	$	5,840
Crude oil	11,834		37,661
Caustic soda	5,690		5,167
NaHS	17,040		9,101
Raw materials - Alkali Operations	7,599		7,120
Work-in-process - Alkali Operations	7,496		9,355
Finished goods, net - Alkali Operations	13,681		13,002
Materials and supplies, net - Alkali Operations	13,620		12,631
Total	$	77,958	$	99,877

Inventories are valued at the lower of cost or net realizable value. The net realizable value of inventories were below cost by $2.0 million as of December 31, 2021, which triggered a reduction of the value of inventory in our Consolidated Financial Statements by this amount. We recorded $5.0 million in inventory reduction adjustments as of December 31, 2020.

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.