Reconciliation of Basic and Diluted Shares (Tables)

9 Months Ended

Sep. 30, 2018

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)	2018		2017		2018		2017
Income from continuing operations attributable to Harsco Corporation common stockholders	$	33,184	$	13,669	$	91,357	$	41,571
Weighted-average shares outstanding - basic	80,950		80,637		80,821		80,519
Dilutive effect of stock-based compensation	2,929		2,499		2,869		2,234
Weighted-average shares outstanding - diluted	83,879		83,136		83,690		82,753
Earnings from continuing operations per common share, attributable to Harsco Corporation common stockholders:
Basic	$	0.41	$	0.17	$	1.13	$	0.52
Diluted	$	0.40	$	0.16	$	1.09	$	0.50

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		Nine Months Ended
	September 30		September 30
(In thousands)	2018	2017	2018	2017
Stock options	—	55	—	55
Stock appreciation rights	75	526	349	918
Performance share units	—	—	—	212