Inventories (Tables)

12 Months Ended

Dec. 31, 2018

Inventory Disclosure [Abstract]

Schedule of Major Components of Inventories

The major components of inventories were as follows:

	December 31,
	2018		2017
Petroleum products	$	12,203	$	8,731
Crude oil	8,379		29,873
Caustic soda	10,372		5,755
NaHS	12,400		8,277
Raw materials - Alkali Operations	5,952		4,550
Work-in-process - Alkali Operations	2,322		7,355
Finished goods, net - Alkali Operations	11,402		14,075
Materials and supplies, net - Alkali Operations	10,490		10,030
Other	11		7
Total	$	73,531	$	88,653