Discontinued Operations and Dispositions - Schedule of Income (Loss) from Discontinued Operations Harsco Rail (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total revenues	$ 609,993	$ 609,016	$ 1,210,310	$ 1,169,721
Selling, general and administrative expenses	90,454	86,801	177,580	168,662
Research and development expenses	943	1,019	1,804	1,539
Other expense (income), net	(7,123)	1,269	(4,683)	6,917
Total costs and expenses	578,738	575,329	1,153,242	1,104,119
Operating income (loss) from continuing operations	31,255	33,687	57,068	65,602
Interest income	3,435	1,594	5,132	3,074
Interest expense	27,934	26,409	56,056	51,404
Defined benefit pension income (expense)	4,166	5,400	8,342	10,729
Income (loss) from continuing operations before income taxes and equity income	(330)	742	(7,907)	1,450
Income tax benefit (expense) from continuing operations	10,020	15,331	17,935	23,348
Income (loss) from continuing operations	(10,223)	(14,898)	(25,964)	(22,340)
Revision of Prior Period, Adjustment
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cost of services and products sold	68,052		119,421
Harsco Rail Segment | Revision of Prior Period, Adjustment
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total revenues	88,848			153,900
Selling, general and administrative expenses	9,951			19,877
Research and development expenses	519			863
Other expense (income), net	954			1,457
Total costs and expenses	79,476			141,618
Operating income (loss) from continuing operations	9,372			12,282
Interest income	27			52
Interest expense	(685)			(1,352)
Defined benefit pension income (expense)	7			13
Income (loss) from continuing operations before income taxes and equity income	8,721			10,995
Income tax benefit (expense) from continuing operations	(5,012)			(6,106)
Income (loss) from continuing operations	3,709			4,889
Service revenues | Harsco Rail Segment | Revision of Prior Period, Adjustment
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total revenues		10,765		18,485
Cost of services and products sold		7,290		12,916
Product Revenues
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total revenues	104,710	127,053	205,873	226,198
Cost of services and products sold	$ 91,996	101,148	$ 177,406	183,697
Product Revenues | Harsco Rail Segment | Revision of Prior Period, Adjustment
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total revenues		78,083		135,415
Cost of services and products sold		$ 60,762		$ 106,505