Goodwill and Other Intangible Assets - Changes in Carrying Amounts of Goodwill by Segment (Details) $ in Thousands	6 Months Ended
Jun. 30, 2019 USD ($)
Goodwill by segment
Goodwill, Other Increase (Decrease)	$ 313,806
Changes in carrying amounts of goodwill
Balance at December 31, 2018	404,713
Foreign currency translation	(792)
Balance at June 30, 2019	717,727
Harsco Environmental Segment
Goodwill by segment
Goodwill, Other Increase (Decrease)	0
Changes in carrying amounts of goodwill
Balance at December 31, 2018	391,687
Foreign currency translation	(792)
Balance at June 30, 2019	390,895
Harsco Clean Earth Segment
Goodwill by segment
Goodwill, Other Increase (Decrease)	313,806
Changes in carrying amounts of goodwill
Balance at December 31, 2018	0
Foreign currency translation	0
Balance at June 30, 2019	313,806
Harsco Rail Segment
Goodwill by segment
Goodwill, Other Increase (Decrease)	0
Changes in carrying amounts of goodwill
Balance at December 31, 2018	13,026
Foreign currency translation	0
Balance at June 30, 2019	$ 13,026

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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-Name Accounting Standards Codification
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