Acquisitions and Dispositions - Financial Information Included in Net Income from Discontinued Operations (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended	9 Months Ended
Jan. 31, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Amounts for the former Harsco Industrial Segment:
Gain on sale of discontinued business	$ 18,400	$ 0	$ 527,980	$ 18,371	$ 527,980
Harsco Industrial \| Discontinued Operations, Held-for-sale
Amounts for the former Harsco Industrial Segment:
Total revenues		0	39,855	10,203	274,037
Cost of products sold		0	28,174	8,082	201,188
Gain on sale of discontinued business		0	527,980	18,371	527,980
Income (loss) from discontinued business		(716)	803	(593)	24,877
Additional amounts allocated to the former Harsco Industrial Segment:
Selling, general and administrative expenses		521	1,994	1,710	5,521
Interest expense		0	0	0	11,237
Loss on extinguishment of debt		$ 0	$ 5,314	$ 0	$ 5,314

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

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