Recently Adopted and Recently Issued Accounting Standards - Consolidated Balance Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Jan. 01, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Current assets:
Trade accounts receivable, net	$ 291,213	$ 288,566	$ 288,034
Inventories	133,111	118,500	178,293
Current portion of contract assets	24,254	18,248	0
Other current assets	35,128	39,511	39,332
Total current assets	605,034	551,258	592,092
Contract assets		3,566
Deferred income tax assets	49,114		51,574
Other assets	17,442	16,600	15,263
Total assets	1,632,867	1,542,754	1,578,685	$ 1,581,338
Current liabilities:
Current portion of advances on contracts	31,317	39,451	117,958
Other current liabilities	118,708	147,363	133,368
Total current liabilities	416,996	409,616	474,128
Advances on contracts	37,675	24,564	0
Other liabilities	46,005	42,426	40,846
Total liabilities	1,319,491	1,325,152	1,363,520
HARSCO CORPORATION STOCKHOLDERS' EQUITY
Accumulated other comprehensive loss	(567,107)	(548,102)	(546,582)
Retained earnings	1,298,752	1,161,758	1,157,801
Total Harsco Corporation stockholders' equity	268,263	172,888	170,451
Noncontrolling interests	45,113		44,714
Total equity	313,376	217,602	215,165	$ 137,563	$ 310,803
Total liabilities and equity	1,632,867	1,542,754	1,578,685
As Reported
Current assets:
Trade accounts receivable, net	303,980		288,034
Inventories	177,621		178,293
Current portion of contract assets	0		0
Other current assets	34,508		39,332
Total current assets	637,437		592,092
Contract assets			0
Deferred income tax assets	51,515
Other assets	15,761		15,263
Total assets	1,665,990		1,578,685
Current liabilities:
Current portion of advances on contracts	117,328		117,958
Other current liabilities	109,259		133,368
Total current liabilities	493,558		474,128
Advances on contracts	0		0
Other liabilities	45,752		40,846
Total liabilities	1,358,125		1,363,520
HARSCO CORPORATION STOCKHOLDERS' EQUITY
Accumulated other comprehensive loss	(566,003)		(546,582)
Retained earnings	1,292,116		1,157,801
Total Harsco Corporation stockholders' equity	262,731		170,451
Noncontrolling interests	45,134
Total equity	307,865		215,165
Total liabilities and equity	1,665,990		1,578,685
Accounting Standards Update 2014-09
HARSCO CORPORATION STOCKHOLDERS' EQUITY
Total equity			$ (548,102)
Accounting Standards Update 2014-09 | Impact of Adoption
Current assets:
Trade accounts receivable, net	12,767	532
Inventories	44,510	(59,793)
Current portion of contract assets	(24,254)	18,248
Other current assets	(620)	179
Total current assets	32,403	(40,834)
Contract assets		3,566
Deferred income tax assets	2,401
Other assets	(1,681)	1,337
Total assets	33,123	(35,931)
Current liabilities:
Current portion of advances on contracts	86,011	(78,507)
Other current liabilities	(9,449)	13,995
Total current liabilities	76,562	(64,512)
Advances on contracts	(37,675)	24,564
Other liabilities	(253)	1,580
Total liabilities	38,634	(38,368)
HARSCO CORPORATION STOCKHOLDERS' EQUITY
Accumulated other comprehensive loss	1,104	(1,520)
Retained earnings	(6,636)	3,957
Total Harsco Corporation stockholders' equity	(5,532)	2,437
Noncontrolling interests	21
Total equity	(5,511)	2,437
Total liabilities and equity	$ 33,123	$ (35,931)