Review of Operations by Segment (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Operations by segment
Revenues	$ 398,841	$ 329,902
Operating income from continuing operations	2,881	19,824
Interest income	193	533
Interest expense	(12,649)	(5,507)
Unused debt commitment and amendment fees	(488)	0
Defined benefit pension income (expense)	1,589	(1,338)
Income (loss) from continuing operations before income taxes and equity income	(8,474)	13,512
Depreciation and Amortization	36,281	31,224
Capital Expenditures	27,787	34,232
Operating Segments
Operations by segment
Operating income from continuing operations	21,237	29,886
Corporate
Operations by segment
Operating income from continuing operations	(18,356)	(10,062)
Depreciation and Amortization	1,152	1,352
Capital Expenditures	58	1,153
Harsco Environmental Segment \| Operating Segments
Operations by segment
Revenues	241,559	261,312
Operating income from continuing operations	10,520	24,497
Depreciation and Amortization	27,311	28,705
Capital Expenditures	24,748	29,163
Harsco Clean Earth Segment \| Operating Segments
Operations by segment
Revenues	78,812	0
Operating income from continuing operations	4,245	0
Depreciation and Amortization	6,519	0
Capital Expenditures	1,442	0
Harsco Rail Segment \| Operating Segments
Operations by segment
Revenues	78,470	68,590
Operating income from continuing operations	6,472	5,389
Depreciation and Amortization	1,299	1,167
Capital Expenditures	$ 1,539	$ 3,916

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