Reconciliation of Basic and Diluted Shares (Tables)

3 Months Ended

Mar. 31, 2020

Earnings Per Share [Abstract]

Reconciliation of basic and diluted shares

	Three Months Ended
	March 31
(In thousands, except per share amounts)	2020			2019
Income (loss) from continuing operations attributable to Harsco Corporation common stockholders	$	(8,782	)	$	10,474
Weighted-average shares outstanding:
Weighted-average shares outstanding - basic	78,761			79,907
Dilutive effect of stock-based compensation	—			1,746
Weighted-average shares outstanding - diluted	78,761			81,653
Earnings (loss) from continuing operations per common share, attributable to Harsco Corporation common stockholders:
Basic	$	(0.11	)	$	0.13
Diluted	$	(0.11	)	$	0.13

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 antidilutive:

	Three Months Ended
	March 31
(In thousands)	2020	2019
Restricted stock units	749	—
Stock appreciation rights	2,643	608
Performance share units	940	233