| Document and Entity Information | Jun. 26, 2020 |
| Cover [Abstract] | |
| Entity Registrant Name | HARSCO CORP |
| Amendment Flag | false |
| Entity Central Index Key | 0000045876 |
| Document Type | 8-K |
| Document Period End Date | Jun. 26, 2020 |
| Entity Incorporation State Country Code | DE |
| Entity File Number | 001-03970 |
| Entity Tax Identification Number | 23-1483991 |
| Entity Address, Address Line One | 350 Poplar Church Road |
| Entity Address, City or Town | Camp Hill |
| Entity Address, State or Province | PA |
| Entity Address, Postal Zip Code | 17011 |
| City Area Code | (717) |
| Local Phone Number | 763-7064 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Security 12b Title | Common stock, par value $1.25 per share |
| Trading Symbol | HSC |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | false |
