Dispositions - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Network Rail
Business Acquisition [Line Items]
Percentage complete	51.00%		51.00%
Reversal of loss on contracts	$ (23.6)
Revenue reduction		$ 0.3		$ 24.5
Deutsche Bahn
Business Acquisition [Line Items]
Percentage complete	38.00%		38.00%
Contract estimated forward loss provision for Harsco Rail Segment	$ (8.4)			(7.4)
SBB
Business Acquisition [Line Items]
Contract estimated forward loss provision for Harsco Rail Segment	$ (6.1)			(3.5)
SBB | Contract
Business Acquisition [Line Items]
Percentage complete	83.00%		83.00%
Discontinued Operations, Held-for-sale | Harsco Rail Segment
Business Acquisition [Line Items]
Corporate overhead expenses	$ 1.1	$ 1.1	$ 2.1	$ 2.1