Equity Method Investments (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Nov. 30, 2013	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Schedule of Equity Method Investments [Line Items]
Decrease in equity method investment			$ 29,400
Harsco's equity in income of Brand		$ 0	5,686	$ 175
Net sales proceeds			145,000
Merger related costs		0	20,640	7,688
Change in fair value to unit adjustment liability			4,700	(8,500)
Unit adjustment liability, current and non-current		$ 0	0
Unit adjustment liability
Schedule of Equity Method Investments [Line Items]
Decrease in unit adjustment liability			19,145
Loss on sale of equity interest			65,461
Infrastructure Transaction Strategic Venture
Schedule of Equity Method Investments [Line Items]
Total annual payments, pre-tax	$ 22,000
Total annual payments, after-tax	$ 15,000
Ownership interest, joint venture contingency threshold	3.00%
Harsco's equity in income of Brand			5,686	$ 175
Accrued liabilities			1,400
Loss on sale of equity interest			43,500
Infrastructure Transaction Strategic Venture | Harsco Infrastructure
Schedule of Equity Method Investments [Line Items]
Harsco's equity in income of Brand			$ (10,300)
Percentage of ownership in equity method investments			26.00%