CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021		Sep. 30, 2020
Revenues from continuing operations:
Total revenues	$ 544,301	$ 509,398	$ 1,642,976		$ 1,355,520
Costs and expenses from continuing operations:
Selling, general and administrative expenses	82,090	87,954	247,798		241,224
Research and development expenses	764	568	2,210		2,620
Other (income) expenses, net	(2,835)	3,633	(7,810)		9,074
Total costs and expenses	514,381	504,334	1,552,013		1,345,707
Operating income from continuing operations	29,920	5,064	90,963		9,813
Interest income	618	604	1,841		1,613
Interest expense	(16,004)	(15,794)	(48,854)		(43,396)
Unused debt commitment fees, amendment fees and loss on extinguishment of debt	(198)	0	(5,506)		(1,920)
Defined benefit pension income	3,906	1,859	11,833		5,171
Income (loss) from continuing operations before income taxes and equity income	18,242	(8,267)	50,277		(28,719)
Income tax benefit (expense) from continuing operations	(6,989)	1,654	(19,782)		4,640
Equity income (loss) of unconsolidated entities, net	(293)	9	(488)		176
Income (loss) from continuing operations	10,960	(6,604)	30,007		(23,903)
Discontinued operations:
Gain (loss) on sale of discontinued business	0	0	0		18,371
Loss from discontinued businesses	(1,528)	(1,531)	(4,770)		(1,232)
Income tax benefit (expense) from discontinued businesses	396	(204)	1,236		(9,803)
Income (loss) from discontinued operations, net of tax	(1,132)	(1,735)	(3,534)		7,336
Net income (loss)	9,828	(8,339)	26,473		(16,567)
Less: Net income attributable to noncontrolling interests	(2,264)	(1,239)	(5,386)		(3,472)
Net income (loss) attributable to Harsco Corporation	7,564	(9,578)	21,087		(20,039)
Amounts attributable to Harsco Corporation common stockholders:
Income (loss) from continuing operations, net of tax	8,696	(7,843)	24,621		(27,375)
Income (loss) from discontinued operations, net of tax	(1,132)	(1,735)	(3,534)		7,336
Net income (loss) attributable to Harsco Corporation	$ 7,564	$ (9,578)	$ 21,087		$ (20,039)
Weighted-average shares of common stock outstanding	79,287	79,000	79,214		78,916
Basic earnings (loss) per common share attributable to Harsco Corporation common stockholders:
Continuing operations (in dollars per share)	$ 0.11	$ (0.10)	$ 0.31		$ (0.35)
Discontinued operations (in dollars per share)	(0.01)	(0.02)	(0.04)		0.09
Basic earnings (loss) per share attributable to Harsco Corporation common stockholders (in dollars per share)	$ 0.10	$ (0.12)	$ 0.27	[1]	$ (0.25)	[1]
Diluted weighted-average shares of common stock outstanding (in shares)	80,275	79,000	80,356		78,916
Diluted earnings (loss) per common share attributable to Harsco Corporation common stockholders:
Continuing operations (in dollars per share)	$ 0.11	$ (0.10)	$ 0.31		$ (0.35)
Discontinued operations (in dollars per share)	(0.01)	(0.02)	(0.04)		0.09
Diluted earnings (loss) per share attributable to Harsco Corporation common stockholders (in dollars per share)	$ 0.09	$ (0.12)	$ 0.26	[1]	$ (0.25)	[1]
Products And Services, Service Revenue
Revenues from continuing operations:
Total revenues	$ 438,624	$ 384,506	$ 1,299,805		$ 1,021,738
Costs and expenses from continuing operations:
Cost of services sold	348,243	313,330	1,031,258		835,879
Product Revenues
Revenues from continuing operations:
Total revenues	105,677	124,892	343,171		333,782
Costs and expenses from continuing operations:
Cost of services sold	$ 86,119	$ 98,849	$ 278,557		$ 256,910

[1] Does not total due to rounding.