Acquisitions and Dispositions - Dispositions Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Jan. 01, 2020
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from Divestiture of Businesses	$ 37,219	$ 0
Receivable with Imputed Interest, Face Amount	40,000
Receivables, Fair Value Disclosure	$ 31,000		$ 34,300
Harsco Industrial IKG [Member] | Disposal Group, Disposed of by Sale, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Selling price			85,000
Disposal Group, Net Gain on Disposal, After Tax			18,500
Disposal Group, Net Gain on Disposal			$ 9,000
Harsco Industrial | Discontinued Operations, Held-for-sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Corporate overhead expenses		$ 1,400