Dispositions - Narrative (Details) - USD ($) $ in Millions	3 Months Ended				9 Months Ended
	Sep. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Business Acquisition [Line Items]
Contract estimated forward loss provision			$ 33.4
Network Rail
Business Acquisition [Line Items]
Contract estimated forward loss provision					$ 24.5
Percentage complete	50.00%				50.00%
Deutsche Bahn
Business Acquisition [Line Items]
Contract estimated forward loss provision		$ 7.4
Percentage complete	29.00%				29.00%
SBB | Contract
Business Acquisition [Line Items]
Contract estimated forward loss provision		$ 3.5
Percentage complete	83.00%				83.00%
Discontinued Operations, Held-for-sale | Harsco Rail Segment
Business Acquisition [Line Items]
Corporate overhead expenses	$ 1.0			$ 1.0	$ 3.1	$ 3.1