Acquisitions and Dispositions - Financial Information Included in Net Income from Discontinued Operations (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Amounts for the former Harsco Industrial Segment:
Gain (loss) on sale of discontinued business	$ 0	$ 0	$ 0	$ 18,371
Harsco Industrial \| Discontinued Operations, Held-for-sale
Amounts for the former Harsco Industrial Segment:
Total revenues	0	0	0	10,203
Cost of products sold	0	0	0	8,082
Gain (loss) on sale of discontinued business	0	0	0	18,371
Income (loss) from discontinued business	(856)	(716)	(2,859)	(593)
Additional amounts allocated to the former Harsco Industrial Segment:
Selling, general and administrative expenses	$ 856	$ 521	$ 2,859	$ 1,710

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

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