Intangible Assets, Goodwill and Other Assets (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Amortization of expense of intangible assets	$ 15,500	$ 18,700	$ 21,800
GOODWILL	301,959	301,959
Sodium minerals and sulfur services
Finite-Lived Intangible Assets [Line Items]
GOODWILL	$ 301,900	$ 301,900
Onshore facilities and transportation | Supply And Logistics Products And Services [Member]
Finite-Lived Intangible Assets [Line Items]
Impairment of goodwill			$ 23,100