Reconciliation of Basic and Diluted Shares (Tables)

9 Months Ended

Sep. 30, 2021

Earnings Per Share [Abstract]

Reconciliation of basic and diluted shares

	Three Months Ended				Nine Months Ended
	September 30				September 30
(In thousands, except per share amounts)	2021		2020		2021		2020
Income (loss) from continuing operations attributable to Harsco Corporation common stockholders	$	8,696	$	(7,843)	$	24,621	$	(27,375)
Weighted-average shares outstanding:
Weighted-average shares outstanding - basic	79,287		79,000		79,214		78,916
Dilutive effect of stock-based compensation	988		—		1,142		—
Weighted-average shares outstanding - diluted	80,275		79,000		80,356		78,916
Earnings (loss) from continuing operations per common share, attributable to Harsco Corporation common stockholders:
Basic	$	0.11	$	(0.10)	$	0.31	$	(0.35)
Diluted	$	0.11	$	(0.10)	$	0.31	$	(0.35)

Schedule of antidilutive securities excluded from computation of earnings per share

The following average outstanding stock-based compensation units were not included in the computation of diluted earnings per share because the effect was either antidilutive or the market conditions for the performance share units were not met:

	Three Months Ended		Nine Months Ended
	September 30		September 30
(In thousands)	2021	2020	2021	2020
Restricted stock units	—	691	—	723
Stock appreciation rights	842	2,383	719	2,499
Performance share units	1,004	857	902	894