Reconciliation of Basic and Diluted Shares (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Reconciliation of Basic and Diluted Shares
Income (loss) from continuing operations attributable to Harsco Corporation common stockholders	$ (28,963)	$ 12,256
Weighted-average shares outstanding - basic	80,579,000	80,695,000
Dilutive effect of stock-based compensation (in shares)		249,000
Weighted-average shares outstanding - diluted	80,579,000	80,944,000
Earnings (loss) from continuing operations per common share, attributable to Harsco Corporation common stockholders:
Basic (in dollars per share)	$ (0.36)	$ 0.15
Diluted (in dollars per share)	$ (0.36)	$ 0.15
Restricted stock units
Antidilutive securities
Number of securities not included in computation of diluted earnings per share (in shares)	63,972
Stock options
Antidilutive securities
Number of securities not included in computation of diluted earnings per share (in shares)	460,000
Stock appreciation rights
Antidilutive securities
Number of securities not included in computation of diluted earnings per share (in shares)	55,992
Other stock-based compensation units
Antidilutive securities
Number of securities not included in computation of diluted earnings per share (in shares)	158,569