Goodwill and Other Intangible Assets - Changes in Carrying Amounts of Goodwill by Segment (Details) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($)
Changes in carrying amounts of goodwill
Balance at December 31, 2018	$ 411,552
Foreign currency translation	897
Balance at March 31, 2019	412,449
Harsco Metals & Minerals Segment
Changes in carrying amounts of goodwill
Balance at December 31, 2018	391,687
Foreign currency translation	897
Balance at March 31, 2019	392,584
Harsco Industrial Segment
Changes in carrying amounts of goodwill
Balance at December 31, 2018	6,839
Foreign currency translation	0
Balance at March 31, 2019	6,839
Harsco Rail Segment
Changes in carrying amounts of goodwill
Balance at December 31, 2018	13,026
Foreign currency translation	0
Balance at March 31, 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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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