Review of Operations by Segment (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Operations by segment
Revenues	$ 447,288	$ 408,038
Operating income from continuing operations	38,246	36,541
Interest income	534	498
Interest expense	(9,739)	(9,583)
Defined benefit pension income (expense)	1,337	(839)
Income from continuing operations before income taxes and equity income	27,704	28,295
Depreciation and Amortization	33,249	33,352
Capital Expenditures	36,407	26,897
Operating Segments
Operations by segment
Operating income from continuing operations	46,916	42,108
Corporate
Operations by segment
Revenues	0	39
Operating income from continuing operations	(8,670)	(5,567)
Depreciation and Amortization	1,352	1,348
Capital Expenditures	1,153	204
Harsco Metals & Minerals Segment \| Operating Segments
Operations by segment
Revenues	261,312	264,723
Operating income from continuing operations	24,497	27,735
Depreciation and Amortization	28,705	29,085
Capital Expenditures	29,163	25,176
Harsco Industrial Segment \| Operating Segments
Operations by segment
Revenues	117,385	83,598
Operating income from continuing operations	17,030	12,421
Depreciation and Amortization	2,025	1,855
Capital Expenditures	2,175	1,087
Harsco Rail Segment \| Operating Segments
Operations by segment
Revenues	68,591	59,678
Operating income from continuing operations	5,389	1,952
Depreciation and Amortization	1,167	1,064
Capital Expenditures	$ 3,916	$ 430

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