Reconciliation of Basic and Diluted Shares Reconciliation of Basic and Diluted Shares (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Earnings Per Share [Abstract]
Income (loss) from continuing operations, net of tax	$ (8,254)	$ 25,000	$ 13,719	$ 21,912
Weighted-average shares outstanding - basic	80,238	80,918	80,233	80,873
Dilutive effect of stock-based compensation	0	181	130	220
Weighted-average shares outstanding - diluted	80,238	81,099	80,363	81,093
Earnings (loss) from continuing operations per common share, attributable to Harsco Corporation common stockholders:
Basic (in dollars per share)	$ (0.10)	$ 0.31	$ 0.17	$ 0.27
Diluted (in dollars per share)	$ (0.10)	$ 0.31	$ 0.17	$ 0.27