Review of Operations by Segment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Operations by segment
Revenues	$ 524,588	$ 486,914	$ 1,540,409	$ 1,420,763
Operating income from continuing operations	29,775	30,123	83,095	(59,132)
Interest income	1,679	952	4,701	2,289
Interest expense	(26,739)	(19,751)	(76,791)	(51,535)
Facility fees and debt-related income (expense)	(2,806)	(2,511)	(7,899)	(894)
Defined benefit pension income (expense)	(5,436)	2,118	(16,178)	6,775
Income (loss) from continuing operations before income taxes and equity income	(3,527)	10,931	(13,072)	(102,497)
Depreciation	35,397	31,892	102,893	97,959
Amortization	8,295	8,538	24,327	25,605
Capital Expenditures	27,010	39,392	92,115	100,151
Operating Segments
Operations by segment
Operating income from continuing operations	39,364	39,432	113,887	(31,719)
Operating Segments | Harsco Environmental Segment
Operations by segment
Revenues	285,877	264,717	848,659	804,367
Operating income from continuing operations	17,867	22,117	52,885	63,931
Depreciation	28,793	26,772	84,707	82,311
Amortization	1,013	1,619	3,020	5,161
Capital Expenditures	20,735	31,688	75,826	80,063
Operating Segments | Clean Earth Segment
Operations by segment
Revenues	238,711	222,197	691,750	616,396
Operating income from continuing operations	21,497	17,315	61,002	(95,650)
Depreciation	6,054	4,576	16,528	14,213
Amortization	6,330	6,071	18,472	18,277
Capital Expenditures	6,186	6,331	15,990	16,577
Corporate
Operations by segment
Operating income from continuing operations	(9,589)	(9,309)	(30,792)	(27,413)
Depreciation	550	544	1,658	1,435
Amortization	952	848	2,835	2,167
Capital Expenditures	$ 89	$ 1,373	$ 299	$ 3,511