Components of Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Components of Accumulated Other Comprehensive Income [Roll Forward]
Balances	$ 137,563	$ 310,803
Other comprehensive income (loss) before reclassifications	12,238	13,306
Amounts reclassified from accumulated other comprehensive loss	5,147	3,833
Realized (gains) losses reclassified from accumulated other comprehensive loss in connection with loss on dilution of equity method investment (See Note 4, Equity Method Investments)		3,037
Other comprehensive income (loss) from equity method investee		(529)
Total other comprehensive income	17,385	19,647
Less: Other Comprehensive loss attributable to noncontrolling interests	(386)	(271)
Other comprehensive income (loss) attributable to Harsco Corporation	16,999	19,376
Balances	168,533	322,333
Cumulative Foreign Exchange Translation Adjustments
Components of Accumulated Other Comprehensive Income [Roll Forward]
Balances	(144,534)	(125,561)
Other comprehensive income (loss) before reclassifications	16,561	9,501
Amounts reclassified from accumulated other comprehensive loss	0	0
Realized (gains) losses reclassified from accumulated other comprehensive loss in connection with loss on dilution of equity method investment (See Note 4, Equity Method Investments)		3,079
Other comprehensive income (loss) from equity method investee		(959)
Total other comprehensive income	16,561	11,621
Less: Other Comprehensive loss attributable to noncontrolling interests	(386)	(267)
Other comprehensive income (loss) attributable to Harsco Corporation	16,175	11,354
Balances	(128,359)	(114,207)
Effective Portion of Deriviatives Designated as Hedging Instruments
Components of Accumulated Other Comprehensive Income [Roll Forward]
Balances	(1,089)	(400)
Other comprehensive income (loss) before reclassifications	(536)	(2,356)
Amounts reclassified from accumulated other comprehensive loss	149	(300)
Realized (gains) losses reclassified from accumulated other comprehensive loss in connection with loss on dilution of equity method investment (See Note 4, Equity Method Investments)		106
Other comprehensive income (loss) from equity method investee		143
Total other comprehensive income	(387)	(2,407)
Less: Other Comprehensive loss attributable to noncontrolling interests	0	(4)
Other comprehensive income (loss) attributable to Harsco Corporation	(387)	(2,411)
Balances	(1,476)	(2,811)
Cumulative Unrecognized Actuarial Losses on Pension Obligations
Components of Accumulated Other Comprehensive Income [Roll Forward]
Balances	(461,094)	(389,696)
Other comprehensive income (loss) before reclassifications	(3,793)	6,168
Amounts reclassified from accumulated other comprehensive loss	4,998	4,133
Realized (gains) losses reclassified from accumulated other comprehensive loss in connection with loss on dilution of equity method investment (See Note 4, Equity Method Investments)		(148)
Other comprehensive income (loss) from equity method investee		287
Total other comprehensive income	1,205	10,440
Less: Other Comprehensive loss attributable to noncontrolling interests	0	0
Other comprehensive income (loss) attributable to Harsco Corporation	1,205	10,440
Balances	(459,889)	(379,256)
Unrealized Loss on Marketable Securities
Components of Accumulated Other Comprehensive Income [Roll Forward]
Balances	(5)	(31)
Other comprehensive income (loss) before reclassifications	6	(7)
Amounts reclassified from accumulated other comprehensive loss	0	0
Realized (gains) losses reclassified from accumulated other comprehensive loss in connection with loss on dilution of equity method investment (See Note 4, Equity Method Investments)		0
Other comprehensive income (loss) from equity method investee		0
Total other comprehensive income	6	(7)
Less: Other Comprehensive loss attributable to noncontrolling interests	0	0
Other comprehensive income (loss) attributable to Harsco Corporation	6	(7)
Balances	1	(38)
Accumulated Other Comprehensive Loss
Components of Accumulated Other Comprehensive Income [Roll Forward]
Balances	(606,722)	(515,688)
Total other comprehensive income	16,999	19,376
Balances	$ (589,723)	$ (496,312)