v3.26.1
Revenues - Revenues by Primary Geographical Markets (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Disaggregation of Revenue [Line Items]    
Total revenues $ 549,803 $ 547,907
Environmental services related to resource recovery for metals manufacturing and related logistical services    
Disaggregation of Revenue [Line Items]    
Total revenues 240,425 227,205
Ecoproducts    
Disaggregation of Revenue [Line Items]    
Total revenues 12,213 10,692
Environmental systems for aluminum dross and scrap processing    
Disaggregation of Revenue [Line Items]    
Total revenues 4,079 5,209
Railway Track Maintenance Equipment    
Disaggregation of Revenue [Line Items]    
Total revenues 20,703 33,068
After-market Parts and Services; Safety and Diagnostic Technology    
Disaggregation of Revenue [Line Items]    
Total revenues 28,955 22,915
Railway Contracting Services    
Disaggregation of Revenue [Line Items]    
Total revenues 17,673 13,964
Hazardous waste processing solutions    
Disaggregation of Revenue [Line Items]    
Total revenues 188,807 197,594
Soil and dredged materials processing and reuse solutions    
Disaggregation of Revenue [Line Items]    
Total revenues 36,948 37,260
North America    
Disaggregation of Revenue [Line Items]    
Total revenues 324,471 327,056
Western Europe    
Disaggregation of Revenue [Line Items]    
Total revenues 118,325 124,868
Latin America    
Disaggregation of Revenue [Line Items]    
Total revenues 42,175 33,924
Asia-Pacific    
Disaggregation of Revenue [Line Items]    
Total revenues 34,517 32,511
Middle East and Africa    
Disaggregation of Revenue [Line Items]    
Total revenues 25,533 25,349
Eastern Europe    
Disaggregation of Revenue [Line Items]    
Total revenues 4,782 4,199
Operating Segments    
Disaggregation of Revenue [Line Items]    
Total revenues 549,803 547,907
Operating Segments | Harsco Environmental    
Disaggregation of Revenue [Line Items]    
Total revenues 256,717 243,106
Operating Segments | Harsco Environmental | Environmental services related to resource recovery for metals manufacturing and related logistical services    
Disaggregation of Revenue [Line Items]    
Total revenues 240,425 227,205
Operating Segments | Harsco Environmental | Ecoproducts    
Disaggregation of Revenue [Line Items]    
Total revenues 12,213 10,692
Operating Segments | Harsco Environmental | Environmental systems for aluminum dross and scrap processing    
Disaggregation of Revenue [Line Items]    
Total revenues 4,079 5,209
Operating Segments | Harsco Environmental | Railway Track Maintenance Equipment    
Disaggregation of Revenue [Line Items]    
Total revenues 0 0
Operating Segments | Harsco Environmental | After-market Parts and Services; Safety and Diagnostic Technology    
Disaggregation of Revenue [Line Items]    
Total revenues 0 0
Operating Segments | Harsco Environmental | Railway Contracting Services    
Disaggregation of Revenue [Line Items]    
Total revenues 0 0
Operating Segments | Harsco Environmental | Hazardous waste processing solutions    
Disaggregation of Revenue [Line Items]    
Total revenues 0 0
Operating Segments | Harsco Environmental | Soil and dredged materials processing and reuse solutions    
Disaggregation of Revenue [Line Items]    
Total revenues 0 0
Operating Segments | Harsco Environmental | North America    
Disaggregation of Revenue [Line Items]    
Total revenues 59,098 55,226
Operating Segments | Harsco Environmental | Western Europe    
Disaggregation of Revenue [Line Items]    
Total revenues 96,439 97,644
Operating Segments | Harsco Environmental | Latin America    
Disaggregation of Revenue [Line Items]    
Total revenues 40,553 32,124
Operating Segments | Harsco Environmental | Asia-Pacific    
Disaggregation of Revenue [Line Items]    
Total revenues 30,357 28,564
Operating Segments | Harsco Environmental | Middle East and Africa    
Disaggregation of Revenue [Line Items]    
Total revenues 25,488 25,349
Operating Segments | Harsco Environmental | Eastern Europe    
Disaggregation of Revenue [Line Items]    
Total revenues 4,782 4,199
Operating Segments | Clean Earth    
Disaggregation of Revenue [Line Items]    
Total revenues 225,755 234,854
Operating Segments | Clean Earth | Environmental services related to resource recovery for metals manufacturing and related logistical services    
Disaggregation of Revenue [Line Items]    
Total revenues 0 0
Operating Segments | Clean Earth | Ecoproducts    
Disaggregation of Revenue [Line Items]    
Total revenues 0 0
Operating Segments | Clean Earth | Environmental systems for aluminum dross and scrap processing    
Disaggregation of Revenue [Line Items]    
Total revenues 0 0
Operating Segments | Clean Earth | Railway Track Maintenance Equipment    
Disaggregation of Revenue [Line Items]    
Total revenues 0 0
Operating Segments | Clean Earth | After-market Parts and Services; Safety and Diagnostic Technology    
Disaggregation of Revenue [Line Items]    
Total revenues 0 0
Operating Segments | Clean Earth | Railway Contracting Services    
Disaggregation of Revenue [Line Items]    
Total revenues 0 0
Operating Segments | Clean Earth | Hazardous waste processing solutions    
Disaggregation of Revenue [Line Items]    
Total revenues 188,807 197,594
Operating Segments | Clean Earth | Soil and dredged materials processing and reuse solutions    
Disaggregation of Revenue [Line Items]    
Total revenues 36,948 37,260
Operating Segments | Clean Earth | North America    
Disaggregation of Revenue [Line Items]    
Total revenues 225,755 234,854
Operating Segments | Clean Earth | Western Europe    
Disaggregation of Revenue [Line Items]    
Total revenues 0 0
Operating Segments | Clean Earth | Latin America    
Disaggregation of Revenue [Line Items]    
Total revenues 0 0
Operating Segments | Clean Earth | Asia-Pacific    
Disaggregation of Revenue [Line Items]    
Total revenues 0 0
Operating Segments | Clean Earth | Middle East and Africa    
Disaggregation of Revenue [Line Items]    
Total revenues 0 0
Operating Segments | Clean Earth | Eastern Europe    
Disaggregation of Revenue [Line Items]    
Total revenues 0 0
Operating Segments | Harsco Rail    
Disaggregation of Revenue [Line Items]    
Total revenues 67,331 69,947
Operating Segments | Harsco Rail | Environmental services related to resource recovery for metals manufacturing and related logistical services    
Disaggregation of Revenue [Line Items]    
Total revenues 0 0
Operating Segments | Harsco Rail | Ecoproducts    
Disaggregation of Revenue [Line Items]    
Total revenues 0 0
Operating Segments | Harsco Rail | Environmental systems for aluminum dross and scrap processing    
Disaggregation of Revenue [Line Items]    
Total revenues 0 0
Operating Segments | Harsco Rail | Railway Track Maintenance Equipment    
Disaggregation of Revenue [Line Items]    
Total revenues 20,703 33,068
Operating Segments | Harsco Rail | After-market Parts and Services; Safety and Diagnostic Technology    
Disaggregation of Revenue [Line Items]    
Total revenues 28,955 22,915
Operating Segments | Harsco Rail | Railway Contracting Services    
Disaggregation of Revenue [Line Items]    
Total revenues 17,673 13,964
Operating Segments | Harsco Rail | Hazardous waste processing solutions    
Disaggregation of Revenue [Line Items]    
Total revenues 0 0
Operating Segments | Harsco Rail | Soil and dredged materials processing and reuse solutions    
Disaggregation of Revenue [Line Items]    
Total revenues 0 0
Operating Segments | Harsco Rail | North America    
Disaggregation of Revenue [Line Items]    
Total revenues 39,618 36,976
Operating Segments | Harsco Rail | Western Europe    
Disaggregation of Revenue [Line Items]    
Total revenues 21,886 27,224
Operating Segments | Harsco Rail | Latin America    
Disaggregation of Revenue [Line Items]    
Total revenues 1,622 1,800
Operating Segments | Harsco Rail | Asia-Pacific    
Disaggregation of Revenue [Line Items]    
Total revenues 4,160 3,947
Operating Segments | Harsco Rail | Middle East and Africa    
Disaggregation of Revenue [Line Items]    
Total revenues 45 0
Operating Segments | Harsco Rail | Eastern Europe    
Disaggregation of Revenue [Line Items]    
Total revenues $ 0 $ 0