CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 19,731	$ (24,301)	$ 29,868	$ (33,893)
Other comprehensive income (loss):
Foreign currency translation adjustments, net of deferred income taxes of $1,458 and $(4,977), and $1,851 and $(8,554) for the three and six months ended June 30, 2017 and 2016, respectively	9,825	(14,394)	26,386	(2,773)
Net loss on cash flow hedging instruments, net of deferred income taxes of $611 and $401, and $867 and $415 for the three and six months ended June 30, 2017 and 2016, respectively	(341)	(144)	(728)	(2,551)
Pension liability adjustments, net of deferred income taxes of $(522) and $(571), and $(1,044) and $(1,256) for the three and six months June 30, 2017 and 2016, respectively	(10,348)	21,855	(9,143)	32,295
Unrealized gain (loss) on marketable securities, net of deferred income taxes of $- and $(2), and $(3) and $2 for the three and six months ended June 30, 2017 and 2016, respectively	0	4	6	(3)
Total other comprehensive income (loss)	(864)	7,321	16,521	26,968
Total comprehensive income (loss)	18,867	(16,980)	46,389	(6,925)
Less: Comprehensive income attributable to noncontrolling interests	(1,841)	(1,183)	(3,474)	(2,731)
Comprehensive income (loss) attributable to Harsco Corporation	$ 17,026	$ (18,163)	$ 42,915	$ (9,656)