Dispositions - Schedule of Income (Loss) from Discontinued Operations Harsco Rail (Details) - Discontinued Operations, Held-for-sale - Harsco Rail Segment - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income (loss) from discontinued businesses	$ (720)	$ 3,964	$ 11,346	$ (26,768)
Selling, general and administrative expenses	1,057	376	2,128	3,887
Service revenues
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenues	17,806	8,629	36,291	22,827
Cost of services and products sold	11,425	6,205	24,341	14,729
Product Revenues
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenues	54,574	60,414	189,989	169,891
Cost of services and products sold	$ 50,760	$ 49,049	$ 157,265	$ 174,143

Amount after tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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