Review of Operations by Segment (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Operations by segment
Revenues	$ 423,155	$ 351,563	$ 1,103,955	$ 1,015,910
Operating income from continuing operations	46,745	41,759	84,368	102,551
Interest income	445	575	1,569	1,645
Interest expense	(12,819)	(5,620)	(24,429)	(16,891)
Unused debt commitment and amendment fees	(158)	(125)	(7,593)	(1,159)
Defined benefit pension income (expense)	1,356	(934)	4,166	(2,677)
Income from continuing operations before income taxes and equity income	32,857	37,523	49,749	88,823
Depreciation and Amortization	35,974	31,402	98,321	94,236
Capital Expenditures	54,941	32,915	140,920	85,408
Operating Segments
Operations by segment
Operating income from continuing operations	56,217	48,338	123,123	122,304
Corporate
Operations by segment
Revenues	0	0	0	74
Operating income from continuing operations	(9,472)	(6,579)	(38,755)	(19,753)
Depreciation and Amortization	1,197	1,332	3,966	4,346
Capital Expenditures	109	297	1,549	673
Harsco Environmental Segment \| Operating Segments
Operations by segment
Revenues	260,883	268,881	791,533	805,924
Operating income from continuing operations	32,794	29,338	84,868	92,734
Depreciation and Amortization	27,308	29,007	84,510	86,724
Capital Expenditures	48,348	29,870	122,606	79,469
Harsco Clean Earth Segment \| Operating Segments
Operations by segment
Revenues	87,639	0	87,639	0
Operating income from continuing operations	11,308	0	11,308	0
Depreciation and Amortization	6,193	0	6,193	0
Capital Expenditures	3,204	0	3,204	0
Harsco Rail Segment \| Operating Segments
Operations by segment
Revenues	74,633	82,682	224,783	209,912
Operating income from continuing operations	12,115	19,000	26,947	29,570
Depreciation and Amortization	1,276	1,063	3,652	3,166
Capital Expenditures	$ 3,280	$ 2,748	$ 13,561	$ 5,266

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