Income Taxes (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Income Tax Disclosure [Line Items]
Effective income tax rate (as a percent)	(4.90%)	33.70%	(16.30%)	72.50%
Unrecognized income tax benefits including interest and penalties	$ 28.0		$ 28.0
Portion of unrecognized income tax benefits, expected to be recognized upon settlement of tax examinations and the expiration of various statutes of limitations within next twelve months	4.3		4.3
Divestiture of Harsco Infrastructure Segment
Income Tax Disclosure [Line Items]
Additional tax expense due to the repatriation of foreign earnings that were previously indefinitely reinvested			8
Divestiture of Harsco Infrastructure Segment | Entities included in the Infrastructure transaction
Income Tax Disclosure [Line Items]
Portion of unrecognized income tax benefits, expected to be recognized upon settlement of tax examinations and the expiration of various statutes of limitations within next twelve months	1.0		1.0
Divestiture of Harsco Infrastructure Segment | Certain foreign tax jurisdictions
Income Tax Disclosure [Line Items]
Additional tax expense due to the estimated non-cash long-lived asset impairment charge affecting the realizability of DTA's			$ 11