Inventories (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Inventory Disclosure [Abstract]
Petroleum products	$ 2,721,000	$ 12,203,000
Crude oil	5,271,000	8,379,000
Caustic soda	5,965,000	10,372,000
NaHS	10,845,000	12,400,000
Raw materials - Alkali Operations	6,238,000	5,952,000
Work-in-process - Alkali Operations	8,579,000	2,322,000
Finished goods, net - Alkali Operations	14,168,000	11,402,000
Materials and supplies, net - Alkali Operations	11,350,000	10,490,000
Other	0	11,000
Total	65,137,000	73,531,000
Inventory Write-down	$ 0	$ 1,000,000.0