Review of Operations by Segment (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
Operations by segment
Revenues	$ 447,281	$ 350,898	$ 846,122	$ 680,800
Operating income from continuing operations	1,868	17,799	4,749	37,623	$ 37,623
Interest income	816	591	1,009	1,124
Interest expense	(14,953)	(6,103)	(27,602)	(11,610)
Unused debt commitment and amendment fees	(1,432)	(7,435)	(1,920)	(7,435)
Defined benefit pension income (expense)	(1,723)	1,472	(3,312)	2,810
Income (loss) from continuing operations before income taxes and equity income	(11,978)	3,380	(20,452)	16,892
Capital Expenditures	23,320	51,747	51,107	85,979
Depreciation	31,579	28,523	61,512	59,857
Amortization			15,672	5,792
Amortization Excluding Deferred Financing Costs	9,115	2,600	15,672	5,230
Depreciation Excluding Industrial Segment			61,303	57,117
Operating Segments
Operations by segment
Operating income from continuing operations	21,992	37,020	43,229	66,906
Corporate
Operations by segment
Operating income from continuing operations	(20,124)	(19,221)	(38,480)	(29,283)
Capital Expenditures	324	287	382	1,440
Depreciation	521	718	1,034	1,378
Amortization	764	699	1,403	1,391
Harsco Environmental Segment \| Operating Segments
Operations by segment
Revenues	203,991	269,338	445,550	530,650
Operating income from continuing operations	13,563	27,577	24,083	52,074
Capital Expenditures	18,654	45,095	43,402	74,258
Depreciation	24,663	26,680	50,038	53,517
Amortization	1,921	1,817	3,857	3,685
Harsco Clean Earth Segment \| Operating Segments
Operations by segment
Revenues	161,579	0	240,391	0
Operating income from continuing operations	(202)	0	4,043	0
Capital Expenditures	3,045	0	4,487	0
Depreciation	5,138	0	7,759	0
Amortization	6,347	0	10,245	0
Harsco Rail Segment \| Operating Segments
Operations by segment
Revenues	81,711	81,560	160,181	150,150
Operating income from continuing operations	8,631	9,443	15,103	14,832
Capital Expenditures	1,297	6,365	2,836	10,281
Depreciation	1,257	1,125	2,472	2,222
Amortization	$ 83	$ 84	$ 167	$ 154

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