Revenue Recognition - Revenues by Primary Geographical Markets (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Disaggregation of Revenue [Line Items]
Revenues	$ 495,653	$ 452,797
Environmental services related to resource recovery for metals manufacturing and related logistical services
Disaggregation of Revenue [Line Items]
Revenues	229,361	227,689
Ecoproducts
Disaggregation of Revenue [Line Items]
Revenues	38,402	31,965
Environmental systems for aluminum dross and scrap processing
Disaggregation of Revenue [Line Items]
Revenues	5,426	2,397
Hazardous waste processing solutions
Disaggregation of Revenue [Line Items]
Revenues	186,112	159,007
Soil and dredged materials processing and reuse solutions
Disaggregation of Revenue [Line Items]
Revenues	36,352	31,739
North America
Disaggregation of Revenue [Line Items]
Revenues	300,937	261,825
Western Europe
Disaggregation of Revenue [Line Items]
Revenues	101,386	102,079
Latin America
Disaggregation of Revenue [Line Items]
Revenues	40,955	35,805
Asia-Pacific
Disaggregation of Revenue [Line Items]
Revenues	28,961	28,068
Middle East and Africa
Disaggregation of Revenue [Line Items]
Revenues	18,405	19,886
Eastern Europe
Disaggregation of Revenue [Line Items]
Revenues	5,009	5,134
Operating Segments | Harsco Environmental Segment
Disaggregation of Revenue [Line Items]
Revenues	273,189	262,051
Operating Segments | Harsco Environmental Segment | Environmental services related to resource recovery for metals manufacturing and related logistical services
Disaggregation of Revenue [Line Items]
Revenues	229,361	227,689
Operating Segments | Harsco Environmental Segment | Ecoproducts
Disaggregation of Revenue [Line Items]
Revenues	38,402	31,965
Operating Segments | Harsco Environmental Segment | Environmental systems for aluminum dross and scrap processing
Disaggregation of Revenue [Line Items]
Revenues	5,426	2,397
Operating Segments | Harsco Environmental Segment | Hazardous waste processing solutions
Disaggregation of Revenue [Line Items]
Revenues	0	0
Operating Segments | Harsco Environmental Segment | Soil and dredged materials processing and reuse solutions
Disaggregation of Revenue [Line Items]
Revenues	0	0
Operating Segments | Harsco Environmental Segment | North America
Disaggregation of Revenue [Line Items]
Revenues	78,473	71,079
Operating Segments | Harsco Environmental Segment | Western Europe
Disaggregation of Revenue [Line Items]
Revenues	101,386	102,079
Operating Segments | Harsco Environmental Segment | Latin America
Disaggregation of Revenue [Line Items]
Revenues	40,955	35,805
Operating Segments | Harsco Environmental Segment | Asia-Pacific
Disaggregation of Revenue [Line Items]
Revenues	28,961	28,068
Operating Segments | Harsco Environmental Segment | Middle East and Africa
Disaggregation of Revenue [Line Items]
Revenues	18,405	19,886
Operating Segments | Harsco Environmental Segment | Eastern Europe
Disaggregation of Revenue [Line Items]
Revenues	5,009	5,134
Operating Segments | Harsco Clean Earth Segment
Disaggregation of Revenue [Line Items]
Revenues	222,464	190,746
Operating Segments | Harsco Clean Earth Segment | Environmental services related to resource recovery for metals manufacturing and related logistical services
Disaggregation of Revenue [Line Items]
Revenues	0	0
Operating Segments | Harsco Clean Earth Segment | Ecoproducts
Disaggregation of Revenue [Line Items]
Revenues	0	0
Operating Segments | Harsco Clean Earth Segment | Environmental systems for aluminum dross and scrap processing
Disaggregation of Revenue [Line Items]
Revenues	0	0
Operating Segments | Harsco Clean Earth Segment | Hazardous waste processing solutions
Disaggregation of Revenue [Line Items]
Revenues	186,112	159,007
Operating Segments | Harsco Clean Earth Segment | Soil and dredged materials processing and reuse solutions
Disaggregation of Revenue [Line Items]
Revenues	36,352	31,739
Operating Segments | Harsco Clean Earth Segment | North America
Disaggregation of Revenue [Line Items]
Revenues	222,464	190,746
Operating Segments | Harsco Clean Earth Segment | Western Europe
Disaggregation of Revenue [Line Items]
Revenues	0	0
Operating Segments | Harsco Clean Earth Segment | Latin America
Disaggregation of Revenue [Line Items]
Revenues	0	0
Operating Segments | Harsco Clean Earth Segment | Asia-Pacific
Disaggregation of Revenue [Line Items]
Revenues	0	0
Operating Segments | Harsco Clean Earth Segment | Middle East and Africa
Disaggregation of Revenue [Line Items]
Revenues	0	0
Operating Segments | Harsco Clean Earth Segment | Eastern Europe
Disaggregation of Revenue [Line Items]
Revenues	$ 0	$ 0