Enviri (NVRI) 10-Q 31 Oct 18 2018 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2018	Oct. 26, 2018
Document And Entity Information [Abstract]
Entity Registrant Name	HARSCO CORP
Entity Central Index Key	45,876
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Sep. 30, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Common Stock, Shares Outstanding		80,313,239

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 61,736	$ 62,098
Restricted cash	2,815	4,111
Trade accounts receivable, net	304,165	288,034
Other receivables	55,156	20,224
Inventories	137,768	178,293
Current portion of contract assets	27,870	0
Other current assets	42,068	39,332
Total current assets	631,578	592,092
Property, plant and equipment, net	460,498	479,747
Goodwill	420,351	401,758
Intangible assets, net	83,598	38,251
Contract assets	3,566	0
Deferred income tax assets	39,824	51,574
Other assets	21,002	15,263
Total assets	1,660,417	1,578,685
Current liabilities:
Short-term borrowings	7,655	8,621
Current maturities of long-term debt	7,149	11,208
Accounts payable	149,216	126,249
Accrued compensation	48,617	60,451
Income taxes payable	11,432	5,106
Insurance liabilities	41,436	11,167
Current portion of advances on contracts	43,682	117,958
Other current liabilities	121,887	133,368
Total current liabilities	431,074	474,128
Long-term debt	625,440	566,794
Insurance liabilities	21,761	22,385
Retirement plan liabilities	213,156	259,367
Advances on contracts	10,322	0
Other liabilities	54,273	40,846
Total liabilities	1,356,026	1,363,520
COMMITMENTS AND CONTINGENCIES
HARSCO CORPORATION STOCKHOLDERS' EQUITY
Preferred stock	0	0
Common stock	141,837	141,110
Additional paid-in capital	187,930	180,201
Accumulated other comprehensive loss	(555,291)	(546,582)
Retained earnings	1,252,840	1,157,801
Treasury stock	(765,765)	(762,079)
Total Harsco Corporation stockholders' equity	261,551	170,451
Noncontrolling interests	42,840	44,714
Total equity	304,391	215,165
Total liabilities and equity	$ 1,660,417	$ 1,578,685

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended				9 Months Ended
	Sep. 30, 2018		Sep. 30, 2017		Sep. 30, 2018	Sep. 30, 2017
Revenues from continuing operations:
Total revenues	$ 445,475		$ 384,653		$ 1,285,485	$ 1,152,092
Costs and expenses from continuing operations:
Selling, general and administrative costs	59,297		59,993		175,307	168,315
Research and development expenses	1,720		936		4,377	3,096
Other (income) expenses, net	628		(1,237)		1,570	1,729
Total costs and expenses	388,366		350,024		1,138,210	1,045,707
Operating income from continuing operations	57,109		34,629		147,275	106,385
Interest income	574		610		1,649	1,615
Interest expense	(9,665)		(12,122)		(29,241)	(36,180)
Defined benefit pension income (expense)	928		(680)		2,671	(2,054)
Loss on early extinguishment of debt	(125)		0		(1,159)	0
Income from continuing operations before income taxes	48,821		22,437		121,195	69,766
Income tax expense	(13,833)		(8,270)		(24,043)	(25,757)
Income from continuing operations	34,988		14,167		97,152	44,009
Discontinued operations:
Loss on disposal of discontinued business	(433)		(578)		(274)	(538)
Income tax benefit related to discontinued business	96		207		61	193
Loss from discontinued operations, net of tax	(337)		(371)		(213)	(345)
Net income	34,651		13,796		96,939	43,664
Less: Net income attributable to noncontrolling interests	(1,804)		(498)		(5,795)	(2,438)
Net income attributable to Harsco Corporation	32,847		13,298		91,144	41,226
Amounts attributable to Harsco Corporation common stockholders:
Income from continuing operations, net of tax	33,184		13,669		91,357	41,571
Loss from discontinued operations, net of tax	(337)		(371)		(213)	(345)
Net income attributable to Harsco Corporation	$ 32,847		$ 13,298		$ 91,144	$ 41,226
Weighted-average shares of common stock outstanding (in shares)	80,950		80,637		80,821	80,519
Basic earnings per common share attributable to Harsco Corporation common stockholders:
Continuing operations (in dollars per share)	$ 0.41		$ 0.17		$ 1.13	$ 0.52
Discontinued operations (in dollars per share)	0		0		0	0
Basic earnings (loss) per share attributable to Harsco Corporation common stockholders (in dollars per share)	$ 0.41		$ 0.16	[1]	$ 1.13	$ 0.51	[1]
Diluted weighted-average shares of common stock outstanding (in shares)	83,879		83,136		83,690	82,753
Diluted earnings per common share attributable to Harsco Corporation common stockholders:
Continuing operations (in dollars per share)	$ 0.40		$ 0.16		$ 1.09	$ 0.50
Discontinued operations (in dollars per share)	0		0		0	0
Diluted earnings (loss) per share attributable to Harsco Corporation common stockholders (in dollars per share)	$ 0.39	[1]	$ 0.16		$ 1.09	$ 0.50
Service Revenues [Member]
Revenues from continuing operations:
Total revenues	$ 250,890		$ 246,144		$ 763,815	$ 738,059
Costs and expenses from continuing operations:
Cost of services and products sold	194,459		194,483		589,738	577,200
Product Revenues [Member]
Revenues from continuing operations:
Total revenues	194,585		138,509		521,670	414,033
Costs and expenses from continuing operations:
Cost of services and products sold	$ 132,262		$ 95,849		$ 367,218	$ 295,367
[1]	Does not total due to rounding

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 34,651	$ 13,796	$ 96,939	$ 43,664
Other comprehensive income (loss):
Foreign currency translation adjustments, net of deferred income taxes of $(91) and $(1,747), and $(1,043) and $3,598 for the three and nine months ended September 30, 2018 and 2017, respectively	(3,953)	16,005	(40,157)	42,391
Net gain (loss) on cash flow hedging instruments, net of deferred income taxes of $(306) and $21, and $(2,191) and $888 for the three and nine months ended September 30, 2018 and 2017, respectively	502	2,199	6,081	1,471
Pension liability adjustments, net of deferred income taxes of $(289) and $(523), and $(902) and $(1,567) for the three and nine months ended September 30, 2018 and 2017, respectively	4,668	(7,324)	24,294	(16,467)
Unrealized gain (loss) on marketable securities, net of deferred income taxes of $(3) and $(3), and $5 and $(6) for the three and nine months September 30, 2018 and 2017, respectively	8	5	(19)	11
Total other comprehensive income	1,225	10,885	(9,801)	27,406
Total comprehensive income	35,876	24,681	87,138	71,070
Less: Comprehensive (income) loss attributable to noncontrolling interests	(432)	(1,200)	(3,183)	(4,674)
Comprehensive income attributable to Harsco Corporation	$ 35,444	$ 23,481	$ 83,955	$ 66,396

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement of Comprehensive Income [Abstract]
Foreign currency translation adjustments, deferred income taxes	$ (91)	$ 1,747	$ (1,043)	$ 3,598
Net gain (loss) on cash flow hedging instruments, deferred income taxes	(306)	21	(2,191)	888
Pension liability adjustments, deferred income taxes	(289)	(523)	(902)	(1,567)
Unrealized gain (loss) on marketable securities, deferred income taxes	$ (3)	$ (3)	$ 5	$ (6)

CONDENSED CONSOLIDATED STATEM_4

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Statement of Cash Flows [Abstract]
Noncontrolling Interest - purchase or sale	$ 477	$ (3,412)
Cash flows from operating activities:
Net income	96,939	43,664
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	92,324	91,519
Amortization	7,620	5,989
Deferred income tax expense	1,996	2,018
Dividends from unconsolidated entities	88	93
Other, net	2,485	2,567
Changes in assets and liabilities:
Accounts receivable	(29,022)	(26,633)
Inventories	(18,852)	(30,112)
Contract assets	(10,427)	0
Accounts payable	17,547	9,045
Accrued compensation	(10,438)	979
Advances on contracts	(12,339)	(6,534)
Retirement plan liabilities, net	(28,743)	(17,890)
Other assets and liabilities	(14,164)	8,200
Net cash provided by operating activities	95,014	82,905
Cash flows from investing activities:
Purchases of property, plant and equipment	(91,302)	(64,131)
Purchases of businesses, net of cash acquired	(56,389)	0
Proceeds from sales of assets	9,096	10,746
Net proceeds from settlement of foreign currency forward exchange contracts	3,244	4,450
Net cash used by investing activities	(135,351)	(48,935)
Cash flows from financing activities:
Short-term borrowings, net	(543)	1,915
Current maturities and long-term debt:
Additions	128,158	26,000
Reductions	(75,104)	(65,245)
Dividends paid to noncontrolling interests	(5,446)	(1,783)
Stock-based compensation - Employee taxes paid	(3,685)	(1,607)
Deferred financing costs	(537)	(42)
Other financing activities, net	0	(370)
Net cash provided (used) by financing activities	43,320	(44,544)
Effect of exchange rate changes on cash and cash equivalents, including restricted cash	(4,641)	4,058
Net decrease in cash and cash equivalents, including restricted cash	(1,658)	(6,516)
Cash and cash equivalents, including restricted cash, at beginning of period	66,209	71,879
Cash and cash equivalents, including restricted cash, at end of period	$ 64,551	$ 65,363

CONDENSED CONSOLIDATED STATEM_5

CONDENSED CONSOLIDATED STATEMENTS OF EQUITY (Unaudited) - USD ($) $ in Thousands	Total	Common Stock Issued	Common Stock Treasury	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Noncontrolling Interests
Increase (Decrease) in Stockholders' Equity
Adoption of new accounting standards (See Note 2)	$ 397			$ 1,106	$ (709)
Balances at Dec. 31, 2016	137,563	$ 140,625	$ (760,391)	172,101	1,150,688	$ (606,722)	$ 41,262
Increase (Decrease) in Stockholders' Equity
Net income	43,664				41,226		2,438
Cash dividends declared: noncontrolling interests	(1,783)						(1,783)
Sale of subsidiary shares to noncontrolling interest	(3,412)			(2,242)			(1,170)
Total other comprehensive income (loss), net of deferred income taxes of $(4,131) and $2,913 in 2018 and 2017, respectively	27,406					25,171	2,235
Stock Appreciation Rights exercised, net 27,669 shares and 8,965 shares in 2018 and 2017, respectively	(63)	16	(63)	(16)
Vesting of restricted stock units and other stock grants, net 382,228 shares and 260,497 shares in 2018 and 2017, respectively	(1,544)	452	(1,544)	(452)
Amortization of unearned portion of stock-based compensation, net of forfeitures	7,790			7,790
Balances at Sep. 30, 2017	210,018	141,093	(761,998)	178,287	1,191,205	(581,551)	42,982
Balances at Dec. 31, 2017	215,165	141,110	(762,079)	180,201	1,157,801	(546,582)	44,714
Increase (Decrease) in Stockholders' Equity
Net income	96,939				91,144		5,795
Cash dividends declared: noncontrolling interests	(5,534)						(5,534)
Sale of subsidiary shares to noncontrolling interest	477						477
Total other comprehensive income (loss), net of deferred income taxes of $(4,131) and $2,913 in 2018 and 2017, respectively	(9,801)					(7,189)	(2,612)
Stock Appreciation Rights exercised, net 27,669 shares and 8,965 shares in 2018 and 2017, respectively	(273)	49	(273)	(49)
Vesting of restricted stock units and other stock grants, net 382,228 shares and 260,497 shares in 2018 and 2017, respectively	(3,413)	678	(3,413)	(678)
Amortization of unearned portion of stock-based compensation, net of forfeitures	8,456			8,456
Balances at Sep. 30, 2018	$ 304,391	$ 141,837	$ (765,765)	$ 187,930	1,252,840	$ (555,291)	$ 42,840
Increase (Decrease) in Stockholders' Equity
Adoption of new accounting standards (See Note 2)					$ 100

CONDENSED CONSOLIDATED STATEM_6

CONDENSED CONSOLIDATED STATEMENTS OF EQUITY (Unaudited) (Parenthetical) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Statement of Stockholders' Equity [Abstract]
Other Comprehensive Income (Loss), Tax	$ (4,131)	$ 2,913
Vesting of restricted stock units and other (in shares)	382,228	260,497
Stock Appreciation Rights exercise (in shares)	27,669	8,965

Basis of Presentation

Basis of Presentation	9 Months Ended
	Sep. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation Harsco Corporation (the "Company") has prepared these unaudited condensed consolidated financial statements in accordance with accounting principles generally accepted in the U.S. (“U.S. GAAP”) for interim financial information and with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X of the Securities and Exchange Commission (the “SEC”). Accordingly, the unaudited condensed consolidated financial statements do not include all information and disclosure required by U.S. GAAP for annual financial statements. The December 31, 2017 Condensed Consolidated Balance Sheet information contained in this Quarterly Report on Form 10-Q was derived from the 2017 audited consolidated financial statements. The unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements, including the notes thereto, included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2017 . In the opinion of management, all adjustments (all of which are of a normal recurring nature) that are necessary for a fair statement are reflected in the unaudited condensed consolidated financial statements. Reclassifications

Recently Adopted and Recently I

Recently Adopted and Recently Issued Accounting Standards	9 Months Ended
	Sep. 30, 2018
Accounting Changes and Error Corrections [Abstract]
Recently Adopted and Recently Issued Accounting Standards	Recently Adopted and Recently Issued Accounting Standards The following accounting standards have been adopted in 2018: On January 1, 2018, the Company adopted changes, with subsequent amendments, issued by the Financial Accounting Standards Board ("FASB") related to the recognition of revenue from contracts with customers. The changes clarify the principles for recognizing revenue and develop a common revenue standard. The core principle of the changes is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The adoption of these changes resulted in the following modifications to the Company's revenue recognition process: • Harsco Industrial Segment - The timing of revenue recognition for air-cooled heat exchanger sales, which the Company historically recognized upon the completion of the efforts associated with these arrangements, is now recognized over time with the impact of increasing revenue in earlier periods. This change also impacted the Company's Condensed Consolidated Balance Sheets by decreasing both Inventories and Advances on contracts; and creating a new caption and establishing a balance related to Contract assets. • Harsco Rail Segment - The timing of revenue recognition for certain railway track maintenance equipment sales, which the Company historically recognized upon the completion of the efforts associated with these arrangements, is now recognized over time with the impact of increasing revenue in earlier periods. This change also impacted the Company's Condensed Consolidated Balance Sheets by decreasing both Inventories and Advances on contracts; and creating a new caption and establishing a balance related to Contract assets. In addition, certain advance payments received from customers, which provide a significant benefit of financing and are expected to be outstanding longer than twelve months, are treated as significant financing components to the related transactions and the Company will increase the overall transaction price with a corresponding increase in interest expense. Additionally, the Company's disclosure related to revenue recognition has been expanded in accordance with the FASB changes. Please refer to Note 14, Revenue Recognition for additional information. The Company chose to implement the impact of the FASB changes utilizing the modified retrospective transition method, using the following practical expedients: • The Company has elected to apply the changes only to revenue arrangements that were not completed as of January 1, 2018; and • The Company has elected to reflect the aggregate effect of all contract modifications that occurred prior to the beginning of the earliest reported period when (i) identifying the satisfied and unsatisfied performance obligations; (ii) determining the transaction price; and (iii) allocating the transaction price to the satisfied and unsatisfied performance obligations. Comparative information has not been restated and continues to be reported under U.S. GAAP in effect for those periods. The cumulative effect of the changes made to the Condensed Consolidated Balance Sheet at January 1, 2018 was as follows: (In thousands) Balance at December 31, 2017 Impact of Adoption Balance at January 1, 2018 ASSETS Current assets: Trade accounts receivable, net $ 288,034 $ 532 $ 288,566 Inventories 178,293 (59,793 ) 118,500 Current portion of contract assets — 18,248 18,248 Other current assets 39,332 179 39,511 Total current assets 592,092 (40,834 ) 551,258 Contract assets — 3,566 3,566 Other assets 15,263 1,337 16,600 Total assets 1,578,685 (35,931 ) 1,542,754 LIABILITIES Current liabilities: Current portion of advances on contracts 117,958 (78,507 ) 39,451 Other current liabilities 133,368 13,995 147,363 Total current liabilities 474,128 (64,512 ) 409,616 Advances on contracts — 24,564 24,564 Other liabilities 40,846 1,580 42,426 Total liabilities 1,363,520 (38,368 ) 1,325,152 HARSCO CORPORATION STOCKHOLDERS' EQUITY Accumulated other comprehensive loss (546,582 ) (1,520 ) (548,102 ) Retained earnings 1,157,801 3,957 1,161,758 Total Harsco Corporation stockholders' equity 170,451 2,437 172,888 Total equity 215,165 2,437 217,602 Total liabilities and equity 1,578,685 (35,931 ) 1,542,754 The impact of modifying the Company's Condensed Consolidated Balance Sheet at September 30, 2018 is as follows: September 30, 2018 (In thousands) As Reported Impact of Adoption As Reported - Less Impact of Adoption ASSETS Current assets: Trade accounts receivable, net $ 304,165 $ (535 ) $ 303,630 Inventories 137,768 91,285 229,053 Current portion of contract assets 27,870 (27,870 ) — Other current assets 42,068 (157 ) 41,911 Total current assets 631,578 62,723 694,301 Contract assets 3,566 (3,566 ) — Deferred income tax assets 39,824 1,874 41,698 Other assets 21,002 (1,040 ) 19,962 Total assets 1,660,417 59,991 1,720,408 September 30, 2018 (In thousands) As Reported Impact of Adoption As Reported - Less Impact of Adoption LIABILITIES Current liabilities: Current portion of advances on contracts 43,682 83,121 126,803 Other current liabilities 121,887 (8,608 ) 113,279 Total current liabilities 431,074 74,513 505,587 Advances on contracts 10,322 (10,322 ) — Other liabilities 54,273 (216 ) 54,057 Total liabilities 1,356,026 63,975 1,420,001 HARSCO CORPORATION STOCKHOLDERS' EQUITY Accumulated other comprehensive loss (555,291 ) 1,679 (553,612 ) Retained earnings 1,252,840 (5,671 ) 1,247,169 Total Harsco Corporation stockholders' equity 261,551 (3,992 ) 257,559 Noncontrolling interests 42,840 8 42,848 Total equity 304,391 (3,984 ) 300,407 Total liabilities and equity 1,660,417 59,991 1,720,408 The impact of modifying the Company's Condensed Consolidated Statements of Operations for the three and nine months ended September 30, 2018 are as follows: Three Months Ended September 30, 2018 (In thousands, except per share amounts) As Reported Impact of Adoption As Reported - Less Impact of Adoption Revenues from continuing operations: Services revenues $ 250,890 $ 512 $ 251,402 Product revenues 194,585 (15,411 ) 179,174 Total revenues 445,475 (14,899 ) 430,576 Costs and expenses from continuing operations: Costs of services sold 194,459 1,273 195,732 Costs of products sold 132,262 (11,979 ) 120,283 Selling, general and administrative costs 59,297 66 59,363 Total costs and expenses 388,366 (10,640 ) 377,726 Operating income from continuing operations 57,109 (4,259 ) 52,850 Interest expense (9,665 ) 550 (9,115 ) Income from continuing operations before income taxes 48,821 (3,709 ) 45,112 Income tax (expense) benefit (13,833 ) 932 (12,901 ) Income from continuing operations 34,988 (2,777 ) 32,211 Net income 34,651 (2,777 ) 31,874 Less: Net income attributable to noncontrolling interests (1,804 ) (10 ) (1,814 ) Net income attributable to Harsco Corporation 32,847 (2,787 ) 30,060 Amounts attributable to Harsco Corporation common stockholders: Income from continuing operations, net of tax 33,184 (2,787 ) 30,397 Net income attributable to Harsco Corporation common stockholders 32,847 (2,787 ) 30,060 Basic earnings per share attributable to Harsco Corporation common stockholders: Continuing operations 0.41 (0.03 ) 0.38 Basic earnings per share attributable to Harsco Corporation common stockholders 0.41 (0.03 ) 0.37 Diluted earnings per share attributable to Harsco Corporation common stockholders: Continuing operations 0.40 (0.03 ) 0.36 Diluted earnings per share attributable to Harsco Corporation common stockholders 0.39 (0.03 ) 0.36 Nine Months Ended September 30, 2018 (In thousands, except per share amounts) As Reported Impact of Adoption As Reported - Less Impact of Adoption Revenues from continuing operations: Services revenues $ 763,815 $ 4,182 $ 767,997 Product revenues 521,670 (34,269 ) 487,401 Total revenues 1,285,485 (30,087 ) 1,255,398 Costs and expenses from continuing operations: Costs of services sold 589,738 3,980 593,718 Costs of products sold 367,218 (30,091 ) 337,127 Selling, general and administrative costs 175,307 103 175,410 Total costs and expenses 1,138,210 (26,008 ) 1,112,202 Operating income from continuing operations 147,275 (4,079 ) 143,196 Interest expense (29,241 ) 1,453 (27,788 ) Income from continuing operations before income taxes 121,195 (2,626 ) 118,569 Income tax (expense) benefit (24,043 ) 919 (23,124 ) Income from continuing operations 97,152 (1,707 ) 95,445 Net income 96,939 (1,707 ) 95,232 Less: Net income attributable to noncontrolling interests (5,795 ) (8 ) (5,803 ) Net income attributable to Harsco Corporation 91,144 (1,715 ) 89,429 Amounts attributable to Harsco Corporation common stockholders: Income from continuing operations, net of tax 91,357 (1,715 ) 89,642 Net income attributable to Harsco Corporation common stockholders 91,144 (1,715 ) 89,429 Basic earnings per share attributable to Harsco Corporation common stockholders: Continuing operations 1.13 (0.02 ) 1.11 Basic earnings per share attributable to Harsco Corporation common stockholders 1.13 (0.02 ) 1.11 Diluted earnings per share attributable to Harsco Corporation common stockholders: Continuing operations 1.09 (0.02 ) 1.07 Diluted earnings per share attributable to Harsco Corporation common stockholders 1.09 (0.02 ) 1.07 The impact of modifying the Company's Condensed Consolidated Statements of Cash Flows for the nine months ended September 30, 2018 is as follows: Nine Months Ended September 30, 2018 (In thousands) As Reported Impact of Adoption As Reported - Less Impact of Adoption Cash flows from operating activities: Net income $ 96,939 $ (1,707 ) $ 95,232 Adjustments to reconcile net income to net cash used by operating activities: Deferred income tax expense (benefit) 1,996 (919 ) 1,077 Changes in assets and liabilities: Accounts receivable (29,022 ) 8 (29,014 ) Inventories (18,852 ) (34,923 ) (53,775 ) Contract assets (10,427 ) 10,427 — Advances on contracts (12,339 ) 21,794 9,455 Other assets and liabilities (14,164 ) 5,320 (8,844 ) Net cash used by operating activities 95,014 — 95,014 On January 1, 2018, the Company adopted changes issued by the FASB related to how employers that sponsor defined benefit pension plans and other postretirement plans present the net periodic pension cost ("NPPC") in the statement of operations. Employers are required to report the service cost component in the same line item or items as other compensation costs arising from services rendered by the pertinent employees during the period. Other components of NPPC are required to be presented in the statement of operations separately from the service cost component and outside of the subtotal of income from operations. The changes also allow only the service cost component to be eligible for capitalization. The adoption of these changes resulted in the Company reclassifying $0.7 million and $2.1 million of NPPC expense for the three and nine months ended September 30, 2017 , respectively, from the captions Cost of services sold; Cost of products sold; and Selling, general and administrative expenses to the new caption, Defined benefit pension income (expense) in the Company's Condensed Consolidated Statements of Operations. On January 1, 2018, the Company adopted changes issued by the FASB clarifying when revisions to the terms or conditions of a share-based payment award require an entity to apply modification accounting. The changes require modification accounting only in circumstances when the terms or conditions result in changes to the fair value, vesting conditions or classification of the award as an equity instrument or a liability. The adoption of these changes did not have an impact on the Company's condensed consolidated financial statements. On January 1, 2018, the Company adopted changes issued by FASB which eliminate the requirement to defer the recognition of current and deferred income taxes for an intra-entity asset transfer until the asset has been sold to an outside party. Under the new guidance, an entity should recognize the income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs. The changes resulted in an adjustment to opening retained earnings of less than $0.1 million . The following accounting standards have been issued and become effective for the Company at a future date: In February 2016, the FASB issued changes, with subsequent amendments, in accounting for leases, which become effective for the Company on January 1, 2019. The changes introduce a lessee model that brings most leases onto the balance sheet, which will result in an increase in lease-related assets and liabilities. The changes also align many of the underlying principles of the new lessor model with those in the FASB’s new revenue recognition standard. Furthermore, the changes address other concerns related to the current lease model such as eliminating the requirement in current guidance for an entity to use bright-line tests in determining lease classification. The changes also require lessors to increase the transparency of their exposure to changes in value of their residual assets and how they manage that exposure. The Company has completed an assessment of existing leasing agreements and is in the process of quantifying the impact on the Company’s consolidated financial statements. The Company has elected to adopt these changes on a modified retrospective basis and the practical expedients allowing for adoption on a prospective basis. In addition, the Company is in the process of identifying changes to current business processes and internal controls to support the reporting and disclosure requirements of the new standard. In January 2017, the FASB issued changes that remove the second step of the annual goodwill impairment test, which requires a hypothetical purchase price allocation. The changes provide that the amount of goodwill impairment will be equal to the amount by which a reporting unit’s carrying value exceeds its fair value, not to exceed the carrying amount of goodwill. All other goodwill impairment guidance remains largely unchanged. The same one-step impairment test will be applied to goodwill at all reporting units, even those with zero or negative carrying amounts. Entities will be required to disclose the amount of goodwill at reporting units with zero or negative carrying amounts. The changes become effective for the Company on January 1, 2020. Management has determined that these changes will not have a material impact on the Company's condensed consolidated financial statements. However, should the Company be required to record a goodwill impairment charge in future periods, the amount recorded may differ compared to any amounts that might be recorded under current practice. In August 2017, the FASB issued changes which expand and refine hedge accounting for both financial and non-financial risk components, aligns the recognition and presentation of the effects of hedging instruments and hedged items in the financial statements and includes certain targeted improvements to ease the application of current guidance related to the assessment of hedge effectiveness. The amendments in this update should be applied to hedging relationships existing on the date of adoption, which includes a cumulative-effect adjustment to eliminate any ineffectiveness recorded to accumulated other comprehensive income or loss with a corresponding adjustment to the opening balance of retained earnings as of the beginning of the fiscal year in which adoption occurred. Presentation and disclosure amendments are required to be applied prospectively. The changes become effective for the Company on January 1, 2019. Management is currently evaluating the impact of these changes on its condensed consolidated financial statements. In February 2018, the FASB issued changes which allow entities to reclassify stranded income tax effects resulting from the Tax Cuts and Jobs Act (the “Act”) from accumulated other comprehensive income to retained earnings in their consolidated financial statements. Under the Act, deferred taxes were adjusted to reflect the reduction of the historical corporate income tax rate to the newly enacted corporate income tax rate, which left the tax effects on items within accumulated other comprehensive income stranded at historical tax rates. The changes become effective for the Company on January 1, 2019. The Company had approximately $21 million of stranded income tax effects in accumulated other comprehensive income at December 31, 2017 resulting from the Act which the Company plans to reclassify upon initial adoption of these changes. In August 2018, the FASB issued changes which modify the disclosure requirements for fair value measurements. The amendments in this update remove the requirement to disclose the amount of, and reasons for, transfers between Level 1 and Level 2 of the fair value hierarchy; the policy for timing of transfers between levels; and the valuation processes for Level 3 fair value measurements. The changes require disclosure of changes in unrealized gains and losses for the period included in other comprehensive income (loss) for recurring Level 3 fair value measurements held at the end of the reporting period and the range and weighted average of significant unobservable inputs used to develop Level 3 fair value measurements. The changes become effective for the Company on January 1, 2020. Management is currently evaluating the impact of these changes on its condensed consolidated financial statements. In August 2018, the FASB issued changes which modify the disclosure requirements for employers that sponsor defined benefit pension or other post-retirement plans. The changes remove the requirements to disclose: amounts in accumulated other comprehensive income (loss) expected to be recognized as components of net periodic benefit cost over the next fiscal year; the amount and timing of plan assets expected to be returned to the employer; and the effects of a one-percentage point change in assumed health care cost trend rates. The update also requires disclosure of an explanation of the reasons for significant gains and losses related to changes in the benefit obligation for the period. The changes become effective for the Company on January 1, 2021. Management is currently evaluating the impact of these changes on its condensed consolidated financial statements.

Acquisitions

Acquisitions	9 Months Ended
	Sep. 30, 2018
Business Combinations [Abstract]
Acquisitions	Acquisitions In May 2018, the Company acquired Altek Europe Holdings Limited and its affiliated entities (collectively, "Altek"), a U.K.-based manufacturer of market leading products that enable aluminum producers and recyclers to manage and efficiently extract value from critical waste streams, reduce waste generation and improve operating productivity. The Company acquired Altek, on a debt and cash free basis, for a purchase price of £45 million (approximately $60 million ) in cash, with the potential for up to £25 million (approximately $33 million ) in additional contingent consideration through 2021 subject to the future financial performance of Altek. The preliminary purchase price included an upfront payment of $60.1 million , subject to working capital adjustments and net of cash acquired, as well as contingent consideration with an estimated preliminary fair value of $16.3 million as of the acquisition date. Altek's revenues and operating results have been included in the results of the Harsco Metals & Minerals Segment and were not material to the Company's consolidated results for the three and nine months ended September 30, 2018. The Company incurred approximately $1 million of costs associated with the Altek acquisition in the caption Selling, general and administrative expenses in the Condensed Consolidated Statements of Operations. The fair value recorded for the assets acquired and liabilities assumed for Altek is as follows: Preliminary Valuation (In millions) June 30 2018 Measurement Period Adjustments (a) September 30 Cash and cash equivalents $ 1.7 $ — $ 1.7 Net working capital (1.5 ) 0.2 (1.3 ) Property, plant and equipment 3.3 — 3.3 Intangible assets 52.5 0.2 52.7 Goodwill 20.9 5.8 26.7 Net deferred tax liabilities (8.5 ) — (8.5 ) Other liabilities (0.3 ) — (0.3 ) Total identifiable net assets of Altek $ 68.1 $ 6.2 $ 74.3 (a) The measurement period adjustments did not have a material impact on the Company's previously reported operating results. The goodwill is attributable to strategic benefits, including enhanced operational and financial scale and product and market diversification that the Company expects to realize. The Company expects less than $1.0 million of goodwill to be deductible for income tax purposes. The following table details the preliminary valuation of identifiable intangible assets and amortization periods for Altek: Amortization Period Preliminary Valuation (Dollars in millions) June 30 2018 Measurement Period Adjustments (a) September 30 Customer related 14.2 years $ 11.5 $ 0.1 $ 11.6 Technology related 10.3 years 36.5 0.1 36.6 Trade names 15.0 years 4.5 — 4.5 Total identifiable intangible assets of Altek $ 52.5 $ 0.2 $ 52.7 (a) The measurement period adjustments did not have a material impact on the Company's previously reported operating results. The Company valued the customer related assets, technology related assets, and trade names using an income-based approach that utilized either the multi-period excess earnings method or the relief from royalty method. The preliminary fair value of contingent consideration was estimated using a probability simulation model, which uses assumptions and estimates to forecast a range of outcomes for the contingent consideration. Key inputs to the model include projected earnings before interest, tax, depreciation and amortization; the discount rate; the projection risk neutralization rate; and volatility, which are Level 3 data. The Company will assess these assumptions and estimates on a quarterly basis as additional data impacting the assumptions is obtained. Any changes in the fair value of contingent consideration related to updated assumptions and estimates will be recognized in the Consolidated Statements of Operations during the period in which the change occurs. The following table reflects the changes in the fair value of contingent consideration: (In thousands) Contingent Consideration Balance, June 30, 2018 $ 10,097 Measurement period adjustment (b) 6,177 Fair value adjustment (c) 412 Foreign currency translation (c) (298 ) Balance, September 30, 2018 $ 16,388 (b) Measurement period adjustment was recorded to goodwill on the Condensed Consolidated Balance Sheet. (c) These amounts are recorded in the caption Other (income) expenses, net on the Condensed Consolidated Statements of Operations. The purchase price allocation for this transaction is not final and the fair value of intangible assets, goodwill and contingent consideration may vary from those reflected in the condensed consolidated financial statements at September 30, 2018

Accounts Receivable and Invento

Accounts Receivable and Inventories	9 Months Ended
	Sep. 30, 2018
Accounts Receivable And Inventories
Accounts Receivable and Inventories	Accounts Receivable and Inventories Accounts receivable consist of the following: (In thousands) September 30 December 31 Trade accounts receivable $ 308,278 $ 292,765 Less: Allowance for doubtful accounts (4,113 ) (4,731 ) Trade accounts receivable, net $ 304,165 $ 288,034 Other receivables (a) (b) $ 55,156 $ 20,224 (a) Other receivables include insurance claim receivables, employee receivables, tax claim receivables and other miscellaneous receivables not included in Trade accounts receivable, net. (b) From time to time, based on developments including ongoing negotiations, the Company adjusts insured liabilities with offsetting insurance receivables, with no impact to the Condensed Consolidated Statements of Operations. The provision (benefit) for doubtful accounts related to trade accounts receivable was as follows: Three Months Ended Nine Months Ended September 30 September 30 (In thousands) 2018 2017 2018 2017 Provision (benefit) for doubtful accounts related to trade accounts receivable $ (26 ) $ 4,087 $ (182 ) $ 5,262 Inventories consist of the following: (In thousands) September 30 December 31 Finished goods $ 19,957 $ 26,415 Work-in-process 22,175 24,367 Contracts-in-process (c) — 45,599 Raw materials and purchased parts 72,935 58,943 Stores and supplies 22,701 22,969 Total inventories $ 137,768 $ 178,293 Contracts-in-process consist of the following: (In thousands) December 31 Contract costs accumulated to date $ 73,740 Estimated forward loss provisions for contracts-in-process (d) (28,141 ) Contracts-in-process (c) (e) $ 45,599 (c) The Company has adopted the new revenue recognition standard utilizing the modified retrospective transition method, including use of practical expedients. Amounts previously reported as Contracts-in-progress have been recognized through the related cumulative catch-up adjustment. See Note 2, Recently Adopted and Recently Issued Accounting Standards for additional information. (d) For periods prior to January 1, 2018, to the extent that the estimated forward loss provision exceeds accumulated contract costs it is included in the caption Other current liabilities on the Condensed Consolidated Balance Sheets and amounted to $3.0 million at December 31, 2017 . (e) At December 31, 2017 , the Company had $97.9 million of net customer advances related to SBB contracts. These amounts are included in the caption Current portion of advances on contracts on the Condensed Consolidated Balance Sheets. The Company recognized an initial estimated forward loss provision related to the contracts with the federal railway system of Switzerland ("SBB") of $45.1 million for the year ended December 31, 2016 . The Company recorded an additional forward loss provision of $1.8 million for the nine months ended September 30, 2018 . At September 30, 2018 , the entire remaining estimated forward loss provision of $9.7 million is included in the caption Other current liabilities on the Condensed Consolidated Balance Sheets. The estimated forward loss provision represents the Company's best estimate based on currently available information. It is possible that the Company's overall estimate of costs to complete these contracts may increase, which would result in an additional estimated forward loss provision at such time, but the Company is unable to estimate any further possible loss or range of loss at this time. The Company recognized $5.0 million and $20.4 million of revenues for the contracts with SBB, on an over time basis, utilizing an input method based on costs incurred for the three and nine months ended September 30, 2018 , respectively. The Company did not recognize any revenue for the contracts with SBB for the three and nine months ended September 30, 2017 . For three and nine months ended September 30, 2018 , consolidated product revenue gross margins were not significantly impacted by the revenue recognized under the SBB contracts. The Company is approximately 98% complete on the first contract and 24% complete on the second contract with SBB as of September 30, 2018

Property, Plant and Equipment

Property, Plant and Equipment	9 Months Ended
	Sep. 30, 2018
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	Property, Plant and Equipment Property, plant and equipment consists of the following: (In thousands) September 30 December 31 Land $ 10,874 $ 10,840 Land improvements 15,874 14,996 Buildings and improvements 192,011 198,582 Machinery and equipment 1,554,559 1,599,713 Uncompleted construction 30,608 24,387 Gross property, plant and equipment 1,803,926 1,848,518 Less: Accumulated depreciation (1,343,428 ) (1,368,771 ) Property, plant and equipment, net $ 460,498 $ 479,747

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	9 Months Ended
	Sep. 30, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets	Goodwill and Other Intangible Assets The following table reflects the changes in carrying amounts of goodwill by segment for the nine months ended September 30, 2018 : (In thousands) Harsco Metals & Minerals Segment Harsco Industrial Segment Harsco Rail Segment Consolidated Totals Balance at December 31, 2017 $ 381,893 $ 6,839 $ 13,026 $ 401,758 Changes to goodwill 26,737 (a) — — 26,737 Foreign currency translation (8,144 ) — — (8,144 ) Balance at September 30, 2018 $ 400,486 $ 6,839 $ 13,026 $ 420,351 (a) Changes to goodwill in the Harsco Metals & Minerals Segment relate to the acquisition of Altek. The purchase price allocation is not yet final for this acquisition. See Note 3, Acquisitions. The Company tests for goodwill impairment annually or more frequently if indicators of impairment exist, or if a decision is made to dispose of a business. The Company performs the annual goodwill impairment test as of October 1 and monitors for triggering events on an ongoing basis. The Company determined that, as of September 30, 2018 , no interim goodwill impairment testing was necessary. Intangible assets included in the caption, Intangible assets, net, on the Condensed Consolidated Balance Sheets consist of the following: September 30, 2018 December 31, 2017 (In thousands) Gross Carrying Amount Accumulated Amortization Gross Carrying Amount Accumulated Amortization Customer related (b) $ 137,498 $ 98,834 $ 153,014 $ 121,385 Patents 2,590 2,495 5,825 5,700 Technology related (b) 36,666 1,851 26,131 26,131 Trade names (b) 9,311 1,754 8,317 4,845 Other 5,856 3,389 8,875 5,850 Total $ 191,921 $ 108,323 $ 202,162 $ 163,911 (b) The increase in net Customer related, Technology related and Trade names intangible assets is related to the acquisition of Altek. The purchase price allocation is not yet final for this acquisition. See Note 3, Acquisitions. Amortization expense for intangible assets was as follows: Three Months Ended Nine Months Ended September 30 September 30 (In thousands) 2018 2017 2018 2017 Amortization expense for intangible assets $ 2,395 $ 1,269 $ 5,326 $ 3,868 The estimated amortization expense for the next five fiscal years based on current intangible assets is as follows: (In thousands) 2018 2019 2020 2021 2022 Estimated amortization expense (c) $ 7,900 $ 9,750 $ 9,250 $ 8,800 $ 8,500

Debt and Credit Agreements

Debt and Credit Agreements	9 Months Ended
	Sep. 30, 2018
Debt Disclosure [Abstract]
Debt and Credit Agreements	Debt and Credit Agreements In June 2018, the Company amended the existing Senior Secured Credit Facility in order to, among other things, reduce the interest rate applicable to the Term Loan Facility and to increase the limit of the Revolving Credit Facility. As a result of the amendments, borrowings under the Term Loan Facility now bear interest at a rate per annum of 225 basis points over the adjusted LIBOR rate and the facility limit under the Revolving Credit Facility has increased to $500 million . Additionally, a charge of $1.0 million was recorded during the second quarter of 2018 consisting principally of fees associated with the transaction and the write-off of unamortized deferred financing costs. Incremental fees associated with the transaction were recorded during the third quarter of 2018 bringing the total charge to $1.2 million for the nine months ended

Employee Benefit Plans

Employee Benefit Plans	9 Months Ended
	Sep. 30, 2018
Retirement Benefits [Abstract]
Employee Benefit Plans	Employee Benefit Plans Three Months Ended September 30 Defined Benefit Pension Plans Net Periodic Pension Cost (Benefit) U.S. Plans International Plans (In thousands) 2018 2017 2018 2017 Service costs $ 10 $ 10 $ 401 $ 426 Interest costs 2,391 2,469 5,498 5,843 Expected return on plan assets (3,017 ) (2,620 ) (10,820 ) (10,632 ) Recognized prior service costs — 8 (37 ) 48 Recognized loss 1,302 1,425 3,737 4,130 Defined benefit pension plans net periodic pension cost (benefit) $ 686 $ 1,292 $ (1,221 ) $ (185 ) Nine Months Ended Sept 30 Defined Benefit Pension Plans Net Periodic Pension Cost (Benefit) U.S. Plans International Plans (In thousands) 2018 2017 2018 2017 Service costs $ 31 $ 32 $ 1,195 $ 1,243 Interest costs 7,172 7,408 16,612 17,349 Expected return on plan assets (9,051 ) (7,863 ) (32,661 ) (31,571 ) Recognized prior service costs — 24 (113 ) 139 Recognized loss 3,906 4,276 11,267 12,260 Settlement/curtailment losses 166 — — — Defined benefit pension plans net periodic pension cost (benefit) $ 2,224 $ 3,877 $ (3,700 ) $ (580 ) On January 1, 2018, the Company adopted changes issued by the FASB related to how employers that sponsor defined benefit pension plans and other postretirement plans present NPPC in the statement of operations. Employers are required to report the service cost component in the same line item or items as other compensation costs arising from services rendered by the pertinent employees during the period. Other components of NPPC are required to be presented in the statement of operations separately from the service cost component and outside of the subtotal of income from operations. See Note 2, Recently Adopted and Recently Issued Accounting Standards, for additional details. Three Months Ended Nine Months Ended Company Contributions September 30 September 30 (In thousands) 2018 2017 2018 2017 Defined benefit pension plans (U.S.) $ 5,958 $ 4,112 $ 9,309 $ 5,054 Defined benefit pension plans (International) 3,219 3,038 16,192 14,338 Multiemployer pension plans 492 498 1,512 1,481 Defined contribution pension plans 2,306 3,278 7,888 8,306 The Company's estimate of expected contributions to be paid during the remainder of 2018 for the U.S. and international defined benefit pension plans are $0.5 million and $2.4 million

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Income tax expense related to continuing operations for the three and nine months ended September 30, 2018 was $13.8 million and $24.0 million , respectively and for the three and nine months ended September 30, 2017 was $8.3 million and $25.8 million , respectively. For the nine months ended September 30, 2018, income tax expense was positively affected by an $8.3 million tax benefit arising from the adjustment to certain existing deferred tax asset valuation allowances as the result of the Altek acquisition. An income tax benefit from an uncertain tax position may be recognized when it is more likely than not that the position will be sustained upon examination, based on technical merits, including resolutions of any related appeals or litigation processes. The reserve for uncertain tax positions at September 30, 2018 was $4.6 million , including interest and penalties. Within the next twelve months, it is reasonably possible that $0.9 million of unrecognized income tax benefits will be recognized upon settlement of tax examinations and the expiration of various statutes of limitations. As a result of the changes in the U.S. tax law, the Company recorded a provisional charge of $48.7 million

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Environmental The Company is involved in a number of environmental remediation investigations and cleanups and, along with other companies, has been identified as a “potentially responsible party” for certain waste disposal sites. While each of these matters is subject to various uncertainties, it is probable that the Company will agree to make payments toward funding certain of these activities, and it is possible that some of these matters will be decided unfavorably to the Company. The Company has evaluated its potential liability, and its financial exposure is dependent upon such factors as the continuing evolution of environmental laws and regulatory requirements, the availability and application of technology, the allocation of cost among potentially responsible parties, the years of remedial activity required and the remediation methods selected. The Company did not have any material accruals or record any material expenses related to environmental matters during the periods presented. The Company evaluates its liability for future environmental remediation costs on a quarterly basis. Although actual costs to be incurred at identified sites in future periods may vary from the estimates (given inherent uncertainties in evaluating environmental exposures), the Company does not expect that any costs that are reasonably possible to be incurred by the Company in connection with environmental matters in excess of the amounts accrued would have a material adverse effect on the Company's financial condition, results of operations or cash flows. Brazilian Tax Disputes The Company is involved in a number of tax disputes with federal, state and municipal tax authorities in Brazil. These disputes are at various stages of the legal process, including the administrative review phase and the collection action phase, and include assessments of fixed amounts of principal and penalties, plus interest charges that increase at statutorily determined amounts per month and are assessed on the aggregate amount of the principal and penalties. In addition, the losing party, at the collection action or court of appeals phase, could be subject to a charge to cover statutorily mandated legal fees, which are generally calculated as a percentage of the total assessed amounts due, inclusive of penalty and interest. Many of the claims relate to value-added ("ICMS"), services and social security tax disputes. The largest proportion of the assessed amounts relate to ICMS claims filed by the State Revenue Authorities from the State of São Paulo, Brazil (the "SPRA"), encompassing the period from January 2002 to May 2005. In October 2009, the Company received notification of the SPRA’s final administrative decision regarding the levying of ICMS in the State of São Paulo in relation to services provided to a customer in the State between January 2004 and May 2005. As of September 30, 2018 , the principal amount of the tax assessment from the SPRA with regard to this case is approximately $2 million , with penalty, interest and fees assessed to date increasing such amount by an additional $20 million . Any change in the aggregate amount since the Company’s last Annual Report on Form 10-K for the year ended December 31, 2017 is due to an increase in assessed interest and statutorily mandated legal fees for the period, as well as foreign currency translation. On June 4, 2018, the Appellate Court of the State of Sao Paulo ruled in favor of the SPRA, but ruled that the assessed penalty should be reduced to approximately $2 million . After calculating the interest accrued on the penalty, the Company estimates that this ruling reduces the current overall liability for this case to approximately $9 million . The Company has filed a motion for clarification on the ruling, which is still pending before the court. In the event the motion for clarification is unsuccessful, the Company plans to appeal both the liability ruling and the amount assessed. Due to multiple court precedents in the Company’s favor, as well as the Company’s ability to seek clarification as well as appeal, the Company does not believe a loss is probable. Another ICMS tax case involving the SPRA refers to the tax period from January 2002 to December 2003 and has not yet reached the judicial phase. The aggregate amount assessed by the tax authorities in August 2005 was $6.3 million (the amounts with regard to this claim are valued as of the date of the assessment since it has not yet reached the collection phase), composed of a principal amount of $1.5 million , with penalty and interest assessed through that date increasing such amount by an additional $4.8 million . All such amounts include the effect of foreign currency translation. The Company continues to believe that sufficient coverage for these claims exists as a result of the indemnification obligations of the Company's customer and such customer’s pledge of assets in connection with the October 2009 notice, as required by Brazilian law. The Company intends to continue its practice of vigorously defending itself against these tax claims under various alternatives, including judicial appeal. The Company will continue to evaluate its potential liability with regard to these claims on a quarterly basis; however, it is not possible to predict the ultimate outcome of these tax-related disputes in Brazil. No loss provision has been recorded in the Company's condensed consolidated financial statements for the disputes described above because the loss contingency is not deemed probable, and the Company does not expect that any costs that are reasonably possible to be incurred by the Company in connection with Brazilian tax disputes would have a material adverse effect on the Company's financial condition, results of operations or cash flows. Brazilian Labor Disputes The Company is subject to ongoing collective bargaining and individual labor claims in Brazil through the Harsco Metals & Minerals Segment which allege, among other things, the Company's failure to pay required amounts for overtime and vacation at certain sites. The Company is vigorously defending itself against these claims; however, litigation is inherently unpredictable, particularly in foreign jurisdictions. While the Company does not currently expect that the ultimate resolution of these claims will have a material adverse effect on the Company’s financial condition, results of operations or cash flows, it is not possible to predict the ultimate outcome of these labor-related disputes. The Company is continuing to review all known labor claims, and, as of September 30, 2018 and December 31, 2017 , the Company has established reserves of $7.4 million and $9.6 million , respectively, on the Company's Condensed Consolidated Balance Sheets for amounts considered to be probable and estimable. As the Company continues to evaluate these claims and takes actions to address them, the amount of established reserves may be impacted. Customer Disputes The Company may, in the normal course of business, become involved in commercial disputes with subcontractors or customers. Although results of operations and cash flows for a given period could be adversely affected by a negative outcome in these or other lawsuits, claims or proceedings, management believes that the ultimate outcome of any ongoing matters will not have a material adverse effect on the Company's financial condition, results of operations or cash flows. Lima Refinery Litigation On April 8, 2016, Lima Refining Company filed a lawsuit against the Company in the District Court of Harris County, Texas related to a January 2015 explosion at an oil refinery operated by Lima Refining Company. The action seeks approximately $317 million plus interest in property damages, lost profits and business interruption damages. The action alleges the explosion occurred because of a defect in a heat exchange cooler manufactured by Hammco Corporation ("Hammco") in 2009, prior to the Company’s acquisition of Hammco in 2014. The Company is vigorously contesting the allegations against it. The Company has both an indemnity right from the sellers of Hammco and liability insurance coverage under various primary and excess policies that the Company believes will be available, if necessary, to cover substantially all such liability that might ultimately be incurred in the above action. As a result, the Company believes the situation will not result in a net unreimbursed loss. Compliance Matter As previously disclosed, in 2017, the Company undertook an internal investigation, with the assistance of outside counsel, after it became aware of allegations involving an employee and an agent of the Harsco Rail subsidiary in China (“Harsco Rail China”). During this investigation the Company learned about certain payments that potentially violate the Foreign Corrupt Practices Act. Revenues attributed to Harsco Rail China were approximately 2% of the Company’s consolidated revenues for each of the prior three completed fiscal years. The Company has voluntarily self-reported its initial findings to the SEC and the U.S. Department of Justice (the “DOJ”) and intends to fully cooperate with these agencies in their review. Based on information known to date, the Company believes the amount of the potential improper payments are not material to the condensed consolidated financial statements. Any determination that the Company's operations or activities were not in compliance with existing laws or regulations could result in the imposition of fines and penalties. No provision with respect to this matter has been made in the Company’s condensed consolidated financial statements. At this time, the Company cannot predict the outcome or impact of the investigation or the reviews by the SEC and the DOJ. However, based on information available at this time, the Company does not believe any potential liability would be material to the Company's condensed consolidated financial position, although an amount recorded, if any, could be material to the results of operations for the period in which it may be recorded. Other The Company is named as one of many defendants (approximately 90 or more in most cases) in legal actions in the U.S. alleging personal injury from exposure to airborne asbestos over the past several decades. In their suits, the plaintiffs have named as defendants, among others, many manufacturers, distributors and installers of numerous types of equipment or products that allegedly contained asbestos. The Company believes that the claims against it are without merit. The Company has never been a producer, manufacturer or processor of asbestos fibers. Any asbestos-containing part of a Company product used in the past was purchased from a supplier and the asbestos encapsulated in other materials such that airborne exposure, if it occurred, was not harmful and is not associated with the types of injuries alleged in the pending actions. At September 30, 2018 , there were 17,287 pending asbestos personal injury actions filed against the Company. Of those actions, 16,737 were filed in the New York Supreme Court (New York County), 113 were filed in other New York State Supreme Court Counties and 437 were filed in courts located in other states. The complaints in most of those actions generally follow a form that contains a standard damages demand of $20 million or $25 million , regardless of the individual plaintiff’s alleged medical condition, and without identifying any specific Company product. At September 30, 2018 , 16,704 of the actions filed in New York Supreme Court (New York County) were on the Deferred/Inactive Docket created by the court in December 2002 for all pending and future asbestos actions filed by persons who cannot demonstrate that they have a malignant condition or discernible physical impairment. The remaining 33 cases in New York County are pending on the Active or In Extremis Docket created for plaintiffs who can demonstrate a malignant condition or physical impairment. The Company has liability insurance coverage under various primary and excess policies that the Company believes will be available, if necessary, to substantially cover any liability that might ultimately be incurred in the asbestos actions referred to above. The costs and expenses of the asbestos actions are being paid by the Company's insurers. In view of the persistence of asbestos litigation in the U.S., the Company expects to continue to receive additional claims in the future. The Company intends to continue its practice of vigorously defending these claims and cases. At September 30, 2018 , the Company has obtained dismissal in 28,007 cases by stipulation or summary judgment prior to trial. It is not possible to predict the ultimate outcome of asbestos-related actions in the U.S. due to the unpredictable nature of this litigation, and no loss provision has been recorded in the Company's condensed consolidated financial statements because a loss contingency is not deemed probable or estimable. Despite this uncertainty, and although results of operations and cash flows for a given period could be adversely affected by asbestos-related actions, the Company does not expect that any costs that are reasonably possible to be incurred by the Company in connection with asbestos litigation would have a material adverse effect on the Company's financial condition, results of operations or cash flows. As previously disclosed, the Company has had ongoing meetings with the Supreme Council for Environment in Bahrain (“SCE”) over processing a byproduct (“salt cakes”) stored at the Al Hafeerah site. The Company’s Bahrain operations that produced the salt cakes has ceased operations and are owned under a strategic venture for which its strategic venture partner owns a 35% minority interest. An Environmental Impact Assessment and Technical Feasibility Study were approved by the SCE during the first quarter of 2018. The Company has previously established a reserve of $7.0 million, which represents the Company's best estimate of the ultimate costs to be incurred to resolve this matter. The Company continues to evaluate this reserve and any future change in estimated costs could be material to the Company’s results of operations in any one period. On July 27, 2018, Brazil’s Federal and Rio de Janeiro State Public Prosecution Offices (MPF and MPE) filed a Civil Public Action against one of the Company's customers (CSN), the Company’s Brazilian subsidiary, the Municipality of Volta Redonda, Brazil, and the Instituto Estadual do Ambiente (local environmental protection agency) seeking the implementation of various measures to limit and reduce the accumulation of customer-owned slag at the site in Brazil. On August 6, 2018, the 3rd Federal Court in Volta Redonda granted the MPF and MPE an injunction against the same parties requiring, among other things, CSN and the Company’s Brazilian subsidiary to limit the volume of slag sent to the site. Because the customer owns the site and the slag located on the site, the Company believes that complying with this injunction is the steel producer’s responsibility. Nevertheless, if the customer does not comply, the Company’s Brazilian subsidiary, as a party to the injunction, could be assessed fines for non-compliance or could incur other losses related to the issue. The Company does not believe that a loss relating to this matter is probable or estimable at this point. The Company is subject to various other claims and legal proceedings covering a wide range of matters that arose in the ordinary course of business. In the opinion of management, all such matters are adequately covered by insurance or by established reserves, and, if not so covered, are without merit or are of such kind, or involve such amounts, as would not have a material adverse effect on the financial position, results of operations or cash flows of the Company. Insurance liabilities are recorded when it is probable that a liability has been incurred for a particular event and the amount of loss associated with the event can be reasonably estimated. Insurance reserves have been estimated based primarily upon actuarial calculations and reflect the undiscounted estimated liabilities for ultimate losses, including claims incurred but not reported. Inherent in these estimates are assumptions that are based on the Company's history of claims and losses, a detailed analysis of existing claims with respect to potential value, and current legal and legislative trends. If actual claims differ from those projected by management, changes (either increases or decreases) to insurance reserves may be required and would be recorded through income in the period the change was determined. When a recognized liability is covered by third-party insurance, the Company records an insurance claim receivable to reflect the covered liability. Insurance claim receivables are included in Other receivables on the Company's Condensed Consolidated Balance Sheets. See Note 1, Summary of Significant Accounting Policies, to the Consolidated Financial Statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2017

Reconciliation of Basic and Dil

Reconciliation of Basic and Diluted Shares	9 Months Ended
	Sep. 30, 2018
Earnings Per Share [Abstract]
Reconciliation of Basic and Diluted Shares	Reconciliation of Basic and Diluted Shares Three Months Ended Nine Months Ended September 30 September 30 (In thousands, except per share amounts) 2018 2017 2018 2017 Income from continuing operations attributable to Harsco Corporation common stockholders $ 33,184 $ 13,669 $ 91,357 $ 41,571 Weighted-average shares outstanding - basic 80,950 80,637 80,821 80,519 Dilutive effect of stock-based compensation 2,929 2,499 2,869 2,234 Weighted-average shares outstanding - diluted 83,879 83,136 83,690 82,753 Earnings from continuing operations per common share, attributable to Harsco Corporation common stockholders: Basic $ 0.41 $ 0.17 $ 1.13 $ 0.52 Diluted $ 0.40 $ 0.16 $ 1.09 $ 0.50 The following average outstanding stock-based compensation units were not included in the computation of diluted earnings per share because the effect was antidilutive: Three Months Ended Nine Months Ended September 30 September 30 (In thousands) 2018 2017 2018 2017 Stock options — 55 — 55 Stock appreciation rights 75 526 349 918 Performance share units — — — 212

Derivative Instruments, Hedging

Derivative Instruments, Hedging Activities and Fair Value	9 Months Ended
	Sep. 30, 2018
Derivative Instruments, Hedging Activities And Fair Value Disclosure [Abstract]
Derivative Instruments, Hedging Activities and Fair Value	Derivative Instruments, Hedging Activities and Fair Value Derivative Instruments and Hedging Activities The Company uses derivative instruments, including foreign currency exchange forward contracts, interest rate swaps and cross-currency interest rate swaps ("CCIRs"), to manage certain foreign currency and interest rate exposures. Derivative instruments are viewed as risk management tools by the Company and are not used for trading or speculative purposes. All derivative instruments are recorded on the Condensed Consolidated Balance Sheets at fair value. Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (an exit price). The Company utilizes market data or assumptions that the Company believes market participants would use in valuing the asset or liability, including assumptions about risk and the risks inherent in the inputs to the valuation technique. The fair value hierarchy distinguishes between (1) market participant assumptions developed based on market data obtained from independent sources (observable inputs), and (2) an entity’s own assumptions about market participant assumptions based on the best information available in the circumstances (unobservable inputs). The fair value hierarchy consists of three broad levels, which give the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1) and the lowest priority to unobservable inputs (Level 3). The three levels of the fair value hierarchy are described below: • Level 1—Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities. • Level 2—Inputs other than quoted prices included within Level 1 that are observable for the asset or liability, either directly or indirectly, including quoted prices for similar assets or liabilities in active markets; quoted prices for identical or similar assets or liabilities in markets that are not active; inputs other than quoted prices that are observable for the asset or liability (e.g., interest rates); and inputs that are derived principally from or corroborated by observable market data by correlation or other means. • Level 3—Inputs that are both significant to the fair value measurement and unobservable. In instances in which multiple levels of inputs are used to measure fair value, hierarchy classification is based on the lowest level input that is significant to the fair value measurement in its entirety. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment and considers factors specific to the asset or liability. The Company primarily applies the market approach for recurring fair value measurements and endeavors to utilize the best available information. Accordingly, the Company utilizes valuation techniques that maximize the use of observable inputs, such as forward rates, interest rates, the Company’s credit risk and counterparties’ credit risks, and which minimize the use of unobservable inputs. The Company is able to classify fair value balances based on the ability to observe those inputs. Foreign currency exchange forward contracts, interest rate swaps and CCIRs are based upon pricing models using market-based inputs (Level 2). Model inputs can be verified, and valuation techniques do not involve significant management judgment. The fair value of outstanding derivative contracts recorded as assets and liabilities on the Condensed Consolidated Balance Sheets was as follows: (In thousands) Balance Sheet Location Fair Value of Derivatives Designated as Hedging Instruments Fair Value of Derivatives Not Designated as Hedging Instruments Total Fair Value September 30, 2018 Asset derivatives (Level 2): Foreign currency exchange forward contracts Other current assets $ 2,209 $ 7,742 $ 9,951 Interest rate swaps Other current assets 1,900 — 1,900 Interest rate swaps Other assets 3,453 — 3,453 Total $ 7,562 $ 7,742 $ 15,304 Liability derivatives (Level 2): Foreign currency exchange forward contracts Other current liabilities $ 109 $ 1,583 $ 1,692 Interest rate swaps Other liabilities 31 — 31 Total $ 140 $ 1,583 $ 1,723 (In thousands) Balance Sheet Location Fair Value of Derivatives Designated as Hedging Instruments Fair Value of Derivatives Not Designated as Hedging Instruments Total Fair Value December 31, 2017 Asset derivatives (Level 2): Foreign currency exchange forward contracts Other current assets $ 2,329 $ 2,915 $ 5,244 Interest rate swaps Other current assets 464 — 464 Interest rate swaps Other assets 170 — $ 170 Total $ 2,963 $ 2,915 $ 5,878 Liability derivatives (Level 2): Foreign currency exchange forward contracts Other current liabilities $ 153 $ 6,970 $ 7,123 Interest rate swaps Other liabilities 1,368 — 1,368 Total $ 1,521 $ 6,970 $ 8,491 All of the Company's derivatives are recorded in the Condensed Consolidated Balance Sheets at gross amounts and not offset. All of the Company's interest rate swaps, CCIRs and certain foreign currency exchange forward contracts are transacted under International Swaps and Derivatives Association ("ISDA") documentation. Each ISDA master agreement permits the net settlement of amounts owed in the event of default. The Company's derivative assets and liabilities subject to enforceable master netting arrangements resulted in a net asset of $1.3 million and a net liability of $0.2 million at September 30, 2018 and December 31, 2017 , respectively. The effect of derivative instruments in the Condensed Consolidated Statements of Operations and the Condensed Consolidated Statements of Comprehensive Income, was as follows: Derivatives Designated as Hedging Instruments (In thousands) Amount Recognized in Other Comprehensive Income (“OCI”) on Derivative - Effective Portion Location of Amount Reclassified from Accumulated OCI into Income - Effective Portion Amount Reclassified from Accumulated OCI into Income - Effective Portion or Equity Location of Amount Recognized in Income on Derivative - Ineffective Portion and Amount Excluded from Effectiveness Testing Amount Recognized in Income on Derivative - Ineffective Portion and Amount Excluded from Effectiveness Testing Three Months Ended September 30, 2018: Foreign currency exchange forward contracts $ (410 ) Product revenues $ (3 ) $ — Interest rate swaps 1,276 Interest expense (367 ) — Cross-currency interest rate swaps — (a) Interest expense 312 — $ 866 $ (58 ) $ — Three Months Ended September 30, 2017: Foreign currency exchange forward contracts $ 2,333 $ — $ — Interest rate swaps (335 ) — — Cross-currency interest rate swaps (72 ) (a) Interest Expense 252 Cost of services and products sold (103 ) $ 1,926 $ 252 $ (103 ) (In thousands) Amount Recognized in Other Comprehensive Income (“OCI”) on Derivative - Effective Portion Location of Amount Reclassified from Accumulated OCI into Income - Effective Portion Amount Reclassified from Accumulated OCI into Income - Effective Portion or Equity Location of Amount Recognized in Income on Derivative - Ineffective Portion and Amount Excluded from Effectiveness Testing Amount Recognized in Income on Derivative - Ineffective Portion and Amount Excluded from Effectiveness Testing Nine Months Ended September 30, 2018: Foreign currency forward exchange contracts $ 1,369 Product revenues / Cost of services and products sold $ (112 ) $ — Foreign currency forward exchange contracts — Retained earnings (b) (1,520 ) — Interest rate swaps 6,657 Interest expense (602 ) — Cross currency interest rate swaps — Interest expense 960 — $ 8,026 $ (1,274 ) $ — Nine Months Ended September 30, 2017: Foreign currency forward exchange contracts $ 3,096 Product revenues / Cost of services and products sold $ (185 ) $ — Interest rate swaps (2,878 ) — — Cross currency interest rate swaps (195 ) (a) Interest expense 745 Cost of services and products sold (420 ) $ 23 $ 560 $ (420 ) (a) Amounts represent changes in foreign currency translation related to balances in Accumulated other comprehensive loss. (b) The Company has adopted the new revenue recognition standard utilizing the modified retrospective transition method, including use of practical expedients. See Note 2, Recently Adopted and Recently Issued Accounting Standards for additional information. Derivatives Not Designated as Hedging Instruments Location of Gain (Loss) Recognized in Income on Derivative Amount of Gain (Loss) Recognized in Income on Derivative(c) (In thousands) 2018 2017 Three Months Ended September 30: Foreign currency exchange forward contracts Cost of services and products sold $ 3,194 $ (7,025 ) Nine Months Ended September 30: Foreign currency exchange forward contracts Cost of services and products sold $ 13,459 $ (18,764 ) (c) These gains (losses) offset amounts recognized in cost of services and products sold principally as a result of intercompany or third party foreign currency exposures. Foreign Currency Exchange Forward Contracts The Company conducts business in multiple currencies and, accordingly, is subject to the inherent risks associated with foreign exchange rate movements. Foreign currency-denominated assets and liabilities are translated into U.S. dollars at the exchange rates existing at the respective balance sheet dates, and income and expense items are translated at the average exchange rates during the respective periods. The Company uses derivative instruments to hedge cash flows related to foreign currency fluctuations. Foreign currency exchange forward contracts outstanding are part of a worldwide program to minimize foreign currency exchange operating income and balance sheet exposure by offsetting foreign currency exposures of certain future payments between the Company and various subsidiaries, suppliers or customers. The unsecured contracts are with major financial institutions. The Company may be exposed to credit loss in the event of non-performance by the contract counterparties. The Company evaluates the creditworthiness of the counterparties and does not expect default by them. Foreign currency exchange forward contracts are used to hedge commitments, such as foreign currency debt, firm purchase commitments and foreign currency cash flows for certain export sales transactions. Changes in the fair value of derivatives used to hedge foreign currency denominated balance sheet items are reported directly in earnings, along with offsetting transaction gains and losses on the items being hedged. Derivatives used to hedge forecasted cash flows associated with foreign currency commitments may be accounted for as cash flow hedges, as deemed appropriate, if the criteria for hedge accounting are met. Gains and losses on derivatives designated as cash flow hedges are deferred in Accumulated other comprehensive loss, a separate component of equity, and reclassified to earnings in a manner that matches the timing of the earnings impact of the hedged transactions. The ineffective portion of all hedges, if any, is recognized currently in earnings. The recognized gains and losses offset amounts recognized in cost of services and products sold principally as a result of intercompany or third party foreign currency exposures. At September 30, 2018 and December 31, 2017, the notional amounts of foreign currency exchange forward contracts were $652.6 million and $671.9 million , respectively. These contracts are primarily denominated in British pounds sterling and Euros and mature through October 2021 . In addition to foreign currency exchange forward contracts, the Company designates certain loans as hedges of net investments in international subsidiaries. The Company recorded pre-tax net loss of $0.8 million and $7.5 million during the three and nine months ended September 30, 2018 , respectively and pre-tax net gains of $7.6 million and $17.1 million for the three and nine months ended September 30, 2017 , respectively, in Accumulated other comprehensive loss . Interest Rate Swaps The Company uses interest rate swaps in conjunction with certain debt issuances in order to secure a fixed interest rate. Changes in the fair value attributed to the effect of the swaps’ interest spread and changes in the credit worthiness of the counter-parties are recorded in Accumulated other comprehensive loss. In January 2017 and February 2018, the Company entered into a series of interest rate swaps that cover the period from 2018 through 2022 and had the effect of converting $300.0 million of the Term Loan Facility from floating-rate to fixed-rate beginning in 2018. The fixed rates provided by the swaps replace the adjusted LIBOR rate in the interest calculation, ranging from 1.65% for 2018 to 3.12% for 2022. The total notional of the Company's interest rate swaps was $300.0 million as of September 30, 2018 . Cross-Currency Interest Rate Swaps The Company may use CCIRs in conjunction with certain debt issuances in order to secure a fixed local currency interest rate. Under these CCIRs, the Company receives interest based on a fixed or floating U.S. dollar rate and pays interest on a fixed local currency rate based on the contractual amounts in dollars and the local currency, respectively. At maturity, there is also the payment of principal amounts between currencies. Changes in the fair value attributed to the effect of the swaps' interest spread and changes in the credit worthiness of the counter-parties are recorded in Accumulated other comprehensive loss. Changes in value attributed to the effect of foreign currency fluctuations are recorded in the Condensed Consolidated Statements of Operations and offset currency fluctuation effects on the debt principal. The Company had no outstanding CCIRs at September 30, 2018 . Fair Value of Other Financial Instruments The carrying amounts of cash and cash equivalents, accounts receivable, accounts payable, accrued liabilities and short-term borrowings approximate fair value due to the short-term maturities of these assets and liabilities. At September 30, 2018 and December 31, 2017 , the total fair value of long-term debt (excluding deferred financing costs), including current maturities, was $649.0 million and $599.1 million , respectively, compared with a carrying value of $646.5 million and $593.7 million

Review of Operations by Segment

Review of Operations by Segment	9 Months Ended
	Sep. 30, 2018
Segment Reporting [Abstract]
Review of Operations by Segment	Review of Operations by Segment Three Months Ended Nine Months Ended September 30 September 30 (In thousands) 2018 2017 2018 2017 Revenues From Continuing Operations Harsco Metals & Minerals $ 268,881 $ 255,163 $ 805,924 $ 761,503 Harsco Industrial 93,912 78,318 269,575 217,766 Harsco Rail 82,682 51,134 209,912 172,716 Corporate — 38 74 107 Total Revenues From Continuing Operations $ 445,475 $ 384,653 $ 1,285,485 $ 1,152,092 Three Months Ended Nine Months Ended September 30 September 30 (In thousands) 2018 2017 2018 2017 Operating Income (Loss) From Continuing Operations Harsco Metals & Minerals $ 29,338 $ 23,613 $ 92,734 $ 80,834 Harsco Industrial 13,959 12,954 40,550 25,088 Harsco Rail 19,000 4,391 29,570 18,800 Corporate (5,188 ) (6,329 ) (15,579 ) (18,337 ) Total Operating Income From Continuing Operations $ 57,109 $ 34,629 $ 147,275 $ 106,385 Depreciation and Amortization Harsco Metals & Minerals $ 29,007 $ 28,636 $ 86,724 $ 84,444 Harsco Industrial 1,971 1,826 5,708 5,509 Harsco Rail 1,063 1,094 3,166 3,156 Corporate 1,332 1,449 4,346 4,399 Total Depreciation and Amortization $ 33,373 $ 33,005 $ 99,944 $ 97,508 Capital Expenditures Harsco Metals & Minerals $ 29,870 $ 20,994 $ 79,469 $ 58,065 Harsco Industrial 1,891 1,678 5,894 3,226 Harsco Rail 2,748 462 5,266 1,765 Corporate 297 297 673 1,075 Total Capital Expenditures $ 34,806 $ 23,431 $ 91,302 $ 64,131 Reconciliation of Segment Operating Income to Income From Continuing Operations Before Income Taxes Three Months Ended Nine Months Ended September 30 September 30 (In thousands) 2018 2017 2018 2017 Segment operating income $ 62,297 $ 40,958 $ 162,854 $ 124,722 General Corporate expense (5,188 ) (6,329 ) (15,579 ) (18,337 ) Operating income from continuing operations 57,109 34,629 147,275 106,385 Interest income 574 610 1,649 1,615 Interest expense (9,665 ) (12,122 ) (29,241 ) (36,180 ) Defined benefit pension income (expense) 928 (680 ) 2,671 (2,054 ) Loss on early extinguishment of debt (125 ) — (1,159 ) — Income from continuing operations before income taxes $ 48,821 $ 22,437 $ 121,195 $ 69,766

Revenue Recognition

Revenue Recognition	9 Months Ended
	Sep. 30, 2018
Revenue from Contract with Customer [Abstract]
Revenue Recognition	Revenue Recognition The Company recognizes revenues to depict the transfer of promised services and products to customers in an amount that reflects the consideration the Company expects to receive in exchange for those services or products. Service revenues include the service components of the Harsco Metals & Minerals and Harsco Rail Segments. Product revenues include the Harsco Industrial Segment and the product revenues of the Harsco Metals & Minerals and Harsco Rail Segments. Harsco Metals & Minerals - This Segment provides on-site services, under long-term contracts, for material logistics; product quality improvement and resource recovery from iron, steel and metals manufacturing; and also manufactures and sells industrial abrasives and roofing granule products. • Service revenues are recognized over time as the customer simultaneously receives the benefits provided by the Company's performance. The Company utilizes an output method based on work performed (liquid steel tons processed, weight of material handled, etc.) to measure progress, which is deemed to best depict the transfer of value to the customer and revenue earned by the Company. Transaction prices are based on contractual terms, which may include both fixed and variable portions. The fixed portion is recognized as earned (normally monthly) over the contractual period. The variable portion is recognized as services are performed and differs based on the volume of services performed. Given the long-term nature of these arrangements, most contracts permit periodic adjustment of either the variable or both the fixed and variable portions based on the changes in macroeconomic indicators, including changes in commodity prices. Transaction prices, when the standalone selling price is not directly observable, are allocated to performance obligations utilizing an expected cost plus a margin approach. Amounts are typically billed and payable on a monthly basis as services are performed. • Product revenues are recognized at the point when control transfers to the customer. Control generally transfers at the point of shipment for domestic orders and in accordance with the international commercial terms included in contracts for export sales. Transaction prices are based on contractual terms, which are generally fixed and when the standalone selling price is not directly observable, allocated to performance obligations utilizing an adjusted market assessment approach. Amounts are billed and payable upon completion of each transaction. At September 30, 2018, the Harsco Metals & Minerals Segment had remaining, fixed, unsatisfied performance obligations, where the expected contract duration exceeds one-year totaling $147.5 million . Of this amount, $44.6 million is expected to be fulfilled by September 30, 2019, $40.1 million by September 30, 2020, $25.6 million by September 30, 2021, $22.5 million by September 30, 2022 and the remainder thereafter. These amounts exclude any variable fees, fixed fees subject to indexation and any performance obligations expected to be satisfied within one year. The increase in remaining, fixed, unsatisfied performance obligations, where the expected contract duration exceeds one year is primarily attributable to new contracts entered into during the third quarter of 2018. Harsco Industrial - This segment sells air-cooled heat exchangers, metal bar grating configurations and energy-efficient heat transfer products. • For air-cooled heat exchangers, revenue is recognized over time as control is transferred to the customer. Control transfers over time because the air-cooled heat exchangers are customized, have no alternate use and the Company has an enforceable right to payment. The Company utilizes an input method based on costs incurred to measure progress, which is deemed to best depict the transfer of value to the customer and revenue earned by the Company. Transaction prices are based on contractual terms, which are generally fixed, and when the standalone selling price is not directly observable, allocated to performance obligations utilizing an adjusted market assessment approach. The Company may receive periodic payments associated with key milestones with any remaining consideration billed and payable upon completion of the transaction. • For metal bar grating configurations and energy-efficient heat transfer products, revenue is recognized at the point when control transfers to the customer. Control generally transfers at the point of shipment for domestic orders and in accordance with the international commercial terms included in contracts for export sales. Transaction prices are based on contractual terms, which are generally fixed, and when the standalone selling price is not directly observable, allocated to performance obligations utilizing an adjusted market assessment approach. Amounts are billed and payable upon completion of each transaction though advance payments are required in limited circumstances. Harsco Rail - This Segment sells railway track maintenance equipment, after-market parts and provides railway track maintenance services. • For the majority of railway track maintenance equipment sales, revenue is recognized at the point when control transfers to the customer. Control generally transfers at the point of shipment for domestic orders and in accordance with the international commercial terms included in contracts for export sales. In certain railway track maintenance equipment sales, revenue is recognized over time because such equipment is highly customized, has no alternate use and the Company has an enforceable right to payment. In such instances, the Company utilizes an input method based on costs incurred to measure progress, which is deemed to best depict the transfer of value to the customer and revenue earned by the Company. Transaction prices are based on contracted terms, which are generally fixed, and when the standalone selling price is not directly observable, allocated to performance obligations utilizing either the adjusted market assessment or expected cost plus a margin approach. For certain transactions, the Company receives periodic payments associated with key milestones. In limited instances, those payments are intended to provide financing with such transactions being treated as including a significant financing component. Any remaining consideration is billed and payable upon completion of the transaction. • For after-market parts sales, revenue is recognized at the point when control transfers to the customer. Control generally transfer to the customer at the point of shipment for domestic orders and in accordance with the international commercial terms included in contracts for export sales. Transaction prices are based on contracted terms, which are generally fixed, and when the standalone selling price is not directly observable, allocated to performance obligations utilizing an adjusted market assessment approach. Amounts are billed and payable upon completion of each contract. • For railway track maintenance services, revenue is recognized over time as the customer simultaneously receives the benefits provided by the Company's performance. The Company utilizes an appropriate output method based on work performed (feet, miles, shifts worked, etc.) to measure progress, which is deemed to best depict the transfer of value to the customer and revenue earned by the Company. Transaction prices are based on contracted terms, which are generally variable. The variable portion is recognized as services are performed and differs based on the value of services. Given the long-term nature of these arrangements, most contracts permit periodic adjustment based on the changes in macroeconomic indicators. Transaction prices, when the standalone selling price is not directly observable, are allocated to performance obligations utilizing an expected cost plus a margin approach. Amounts are typically billed and payable on a monthly basis as services are performed. At September 30, 2018, the Harsco Rail Segment had remaining, fixed, unsatisfied performance obligations, where the expected contract duration exceeds one-year totaling $200.3 million . Of this amount, $46.6 million is expected to be fulfilled by September 30, 2019, $63.0 million by September 30, 2020, $54.5 million by September 30, 2021, $28.0 million by September 30, 2022 and the remainder thereafter. These amounts exclude any variable fees, fixed fees subject to indexation and any performance obligations expected to be satisfied within one year. The increase in remaining, fixed, unsatisfied performance obligations, where the expected contract duration exceeds one year is primarily attributable to the further satisfaction of performance obligations for over time equipment contracts. A summary of the Company's revenues by primary geographical markets as well as by key product and service groups is as follows: Three Months Ended September 30, 2018 (In thousands) Harsco Metals & Minerals Segment Harsco Industrial Segment Harsco Rail Segment Corporate Consolidated Totals Primary Geographical Markets (a) : North America $ 78,844 $ 88,524 $ 62,823 $ — $ 230,191 Western Europe 97,411 — 10,720 — 108,131 Latin America (b) 36,165 5,388 1,130 — 42,683 Asia-Pacific 36,846 — 8,009 — 44,855 Middle East and Africa 12,370 — — — 12,370 Eastern Europe 7,245 — — — 7,245 Total Revenues (c) $ 268,881 $ 93,912 $ 82,682 $ — $ 445,475 Key Product and Service Groups: On-site services and material logistics, product quality improvement and resource recovery for iron, steel and metals manufacturing; as well as value- added environmental solutions for industrial co-products $ 268,881 $ — $ — $ — $ 268,881 Railway track maintenance services and equipment — — 82,682 — 82,682 Air-cooled heat exchangers — 52,093 — — 52,093 Industrial grating and fencing products — 31,782 — — 31,782 Heat transfer products — 10,037 — — 10,037 Total Revenues (c) $ 268,881 $ 93,912 $ 82,682 $ — $ 445,475 Three Months Ended September 30, 2017 (In thousands) Harsco Metals & Minerals Segment Harsco Industrial Segment Harsco Rail Segment Corporate Consolidated Totals Primary Geographical Markets (a) : North America $ 70,325 $ 72,260 $ 36,112 $ 38 $ 178,735 Western Europe 89,481 — 10,495 — 99,976 Latin America (b) 41,656 5,026 737 — 47,419 Asia-Pacific 35,990 1,032 3,790 — 40,812 Middle East and Africa 10,849 — — — 10,849 Eastern Europe 6,862 — — — 6,862 Total Revenues (c) $ 255,163 $ 78,318 $ 51,134 $ 38 $ 384,653 Key Product and Service Groups: On-site services and material logistics, product quality improvement and resource recovery for iron, steel and metals manufacturing; as well as value- added environmental solutions for industrial co-products $ 255,163 $ — $ — $ — $ 255,163 Railway track maintenance services and equipment — — 51,134 — 51,134 Air-cooled heat exchangers — 38,248 — — 38,248 Industrial grating and fencing products — 29,659 — — 29,659 Heat transfer products — 10,411 — — 10,411 General Corporate — — — 38 38 Total Revenues (c) $ 255,163 $ 78,318 $ 51,134 $ 38 $ 384,653 Nine Months Ended September 30, 2018 (In thousands) Harsco Metals & Minerals Segment Harsco Industrial Segment Harsco Rail Segment Corporate Consolidated Totals Primary Geographical Markets (a) : North America $ 229,771 $ 254,556 $ 150,775 $ 74 $ 635,176 Western Europe 291,742 — 38,481 — 330,223 Latin America (b) 115,011 15,019 3,294 — 133,324 Asia-Pacific 110,855 — 17,362 — 128,217 Middle East and Africa 36,073 — — — 36,073 Eastern Europe 22,472 — — — 22,472 Total Revenues (c) $ 805,924 $ 269,575 $ 209,912 $ 74 $ 1,285,485 Key Product and Service Groups: On-site services and material logistics, product quality improvement and resource recovery for iron, steel and metals manufacturing; as well as value- added environmental solutions for industrial co-products $ 805,924 $ — $ — $ — $ 805,924 Railway track maintenance services and equipment — — 209,912 — 209,912 Air-cooled heat exchangers — 144,936 — — 144,936 Industrial grating and fencing products — 94,325 — — 94,325 Heat transfer products — 30,314 — — 30,314 General Corporate — — — 74 74 Total Revenues (c) $ 805,924 $ 269,575 $ 209,912 $ 74 $ 1,285,485 Nine Months Ended September 30, 2017 (In thousands) Harsco Metals & Minerals Segment Harsco Industrial Segment Harsco Rail Segment Corporate Consolidated Totals Primary Geographical Markets (a) : North America $ 208,317 $ 197,776 $ 130,010 $ 107 $ 536,210 Western Europe 278,717 — 26,866 — 305,583 Latin America (b) 119,434 16,916 1,991 — 138,341 Asia-Pacific 103,306 3,074 13,849 — 120,229 Middle East and Africa 31,358 — — — 31,358 Eastern Europe 20,371 — — — 20,371 Total Revenues (c) $ 761,503 $ 217,766 $ 172,716 $ 107 $ 1,152,092 Key Product and Service Groups: On-site services and material logistics, product quality improvement and resource recovery for iron, steel and metals manufacturing; as well as value- added environmental solutions for industrial co-products $ 761,503 $ — $ — $ — $ 761,503 Railway track maintenance services and equipment — — 172,716 — 172,716 Air-cooled heat exchangers — 102,483 — — 102,483 Industrial grating and fencing products — 86,952 — — 86,952 Heat transfer products — 28,331 — — 28,331 General Corporate — — — 107 107 Total Revenues (c) $ 761,503 $ 217,766 $ 172,716 $ 107 $ 1,152,092 (a) Revenues are attributed to individual countries based on the location of the facility generating the revenue. (b) Includes Mexico. (c) The Company has adopted the new revenue recognition standard utilizing the modified retrospective transition method, including use of practical expedients. Comparative information has not been restated and continues to be reported under U.S. GAAP in effect for those periods. See Note 2, Recently Adopted and Recently Issued Accounting Standards for additional information. The Company may receive payments in advance of earning revenue, which are treated as Advances on contracts on the Condensed Consolidated Balance Sheets. The Company may recognize revenue in advance of being able to contractually invoice the customer, which is treated as Contract assets on the Condensed Consolidated Balance Sheet. Contract assets are transferred to Trade accounts receivable, net when right to payment becomes unconditional. Contract assets and Contract liabilities are reported as a net position, on a contract-by-contract basis, at the end of each reporting period. These instances are primarily related to the Harsco Rail Segment and air-cooled heat exchangers business of the Harsco Industrial Segment. The following table reflects Contract assets and Advances on contracts: (In thousands) September 30, 2018 December 31, 2017 Contract assets: Current portion of contract assets $ 27,870 $ — Contract assets 3,566 — Total contract assets $ 31,436 $ — Advances on contracts: Current portion of advances on contracts $ 43,682 $ 117,958 Advances on contracts 10,322 — Total advances on contracts $ 54,004 $ 117,958 The increase in Contract assets and decrease in Advances on contracts is primarily attributable to the initial adoption of the FASB issued changes related to revenue recognition as well as the Altek acquisition. See Note 2, Recently Adopted and Recently Issued Accounting Standards for additional information. The Company provides assurance type warranties primarily for product sales in the Harsco Industrial and Harsco Rail Segments. These warranties are typically not priced or negotiated separately (there is no option to separately purchase the warranty) or the warranty does not provide customers with a service in addition to the assurance that the product complies with agreed-upon specifications. Accordingly, such warranties do not represent separate performance obligations. See Note 1, Summary of Significant Accounting Policies, to the Consolidated Financial Statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2017 for additional information on warranties. The Company has elected to utilize the following practical expedients on an ongoing basis as part of the adoption: • The Company has not adjusted the promised amount of consideration for the effects of a significant financing component if the Company expects, at contract inception, that the period between when the Company transfers the promised good or services to the customer and when the customer pays for that good or service would be one year or less; and • The Company has elected to exclude disclosures related to unsatisfied performance obligations where the related contract has a duration of one year or less; or where the consideration is entirely variable. Accordingly, the Company's disclosure related to unsatisfied performance obligations is limited to the railway track maintenance equipment in the Harsco Rail Segment and the fixed portion of fees related to metals services in the Harsco Metals & Minerals Segment.

Other (Income) Expenses, Net

Other (Income) Expenses, Net	9 Months Ended
	Sep. 30, 2018
Other Income and Expenses [Abstract]
Other (Income) Expenses	Other (Income) Expenses, Net The major components of this Condensed Consolidated Statements of Operations caption are as follows: Three Months Ended Nine Months Ended September 30 September 30 (In thousands) 2018 2017 2018 2017 Employee termination benefit costs $ 1,037 $ 2,536 $ 3,249 $ 4,947 Net gains (a) (1,262 ) (4,821 ) (2,359 ) (4,815 ) Other costs to exit activities 11 327 475 495 Impaired asset write-downs — 539 113 820 Contingent consideration adjustments 412 — 412 — Other 430 182 (320 ) 282 Other (income) expenses, net $ 628 $ (1,237 ) $ 1,570 $ 1,729 (a) Net gains result from the sales of redundant properties (primarily land, buildings and related equipment) and non-core assets.

Components of Accumulated Other

Components of Accumulated Other Comprehensive Loss	9 Months Ended
	Sep. 30, 2018
Equity [Abstract]
Components of Accumulated Other Comprehensive Loss	Components of Accumulated Other Comprehensive Loss Accumulated other comprehensive loss is included in the Condensed Consolidated Statements of Equity. The components of Accumulated other comprehensive loss, net of the effect of income taxes, and activity for the nine months ended September 30, 2017 and 2018 was as follows: Components of Accumulated Other Comprehensive Income (Loss) - Net of Tax (In thousands) Cumulative Foreign Exchange Translation Adjustments Effective Portion of Derivatives Designated as Hedging Instruments Cumulative Unrecognized Actuarial Losses on Pension Obligations Unrealized Gain (Loss) on Marketable Securities Total Balance at December 31, 2016 $ (144,534 ) $ (1,089 ) $ (461,094 ) $ (5 ) $ (606,722 ) Other comprehensive income (loss) before reclassifications 42,391 (a) 1,133 (b) (31,600 ) (a) 11 11,935 Amounts reclassified from accumulated other comprehensive loss, net of tax — 338 15,133 — 15,471 Total other comprehensive income (loss) 42,391 1,471 (16,467 ) 11 27,406 Other comprehensive loss attributable to noncontrolling interests (2,235 ) — — — (2,235 ) Other comprehensive income (loss) attributable to Harsco Corporation 40,156 1,471 (16,467 ) 11 25,171 Balance at September 30, 2017 $ (104,378 ) $ 382 $ (477,561 ) $ 6 $ (581,551 ) Components of Accumulated Other Comprehensive Income (Loss) - Net of Tax (In thousands) Cumulative Foreign Exchange Translation Adjustments Effective Portion of Derivatives Designated as Hedging Instruments Cumulative Unrecognized Actuarial Losses on Pension Obligations Unrealized Gain (Loss) on Marketable Securities Total Balance at December 31, 2017 $ (111,567 ) $ 808 $ (435,840 ) $ 17 $ (546,582 ) Adoption of new accounting standard (c) — (1,520 ) — — (1,520 ) Balance at January 1, 2018 (111,567 ) (712 ) (435,840 ) 17 (548,102 ) Other comprehensive income (loss) before reclassifications (40,157 ) (a) 6,055 (b) 9,970 (a) (19 ) (24,151 ) Amounts reclassified from accumulated other comprehensive loss, net of tax — 26 14,324 — 14,350 Total other comprehensive income (loss) (40,157 ) 6,081 24,294 (19 ) (9,801 ) Other comprehensive income attributable to noncontrolling interests 2,612 — — — 2,612 Other comprehensive income (loss) attributable to Harsco Corporation (37,545 ) 6,081 24,294 (19 ) (7,189 ) Balance at September 30, 2018 $ (149,112 ) $ 5,369 $ (411,546 ) $ (2 ) $ (555,291 ) (a) Principally foreign currency fluctuation. (b) Net change from periodic revaluations. (c) Represents the opening balance sheet adjustment to retained earnings related to the adoption of the revenue recognition standard adopted by the Company on January 1, 2018. See Note 2, Recently Adopted and Recently Issued Accounting Standards, for additional details. Amounts reclassified from accumulated other comprehensive loss are as follows: (In thousands) Three Months Ended Nine Months Ended Affected Caption in the Condensed Consolidated Statements of Operations September 30 September 30 September 30 September 30 Amortization of cash flow hedging instruments: Foreign currency exchange forward contracts $ (3 ) $ — $ (112 ) $ (189 ) Product revenues Foreign currency exchange forward contracts — — — 4 Cost of services and products sold Cross-currency interest rate swaps 312 252 960 745 Interest expense Interest rate swaps (367 ) — (602 ) — Interest expense Total before tax (58 ) 252 246 560 Tax expense (13 ) (99 ) (220 ) (222 ) Total reclassification of cash flow hedging instruments, net of tax $ (71 ) $ 153 $ 26 $ 338 Amortization of defined benefit pension items (d) : Recognized losses $ 5,039 $ 5,558 $ 15,173 $ 16,536 Defined benefit pension income (expense) Recognized prior-service costs (37 ) 56 (113 ) 163 Defined benefit pension income (expense) Settlement/curtailment losses — — 166 — Defined benefit pension income (expense) Total before tax 5,002 5,614 15,226 16,699 Tax benefit (289 ) (523 ) (902 ) (1,566 ) Total reclassification of defined benefit pension items, net of tax $ 4,713 $ 5,091 $ 14,324 $ 15,133 (d)

Basis of Presentation (Policies

Basis of Presentation (Policies)	9 Months Ended
	Sep. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation Harsco Corporation (the "Company") has prepared these unaudited condensed consolidated financial statements in accordance with accounting principles generally accepted in the U.S. (“U.S. GAAP”) for interim financial information and with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X of the Securities and Exchange Commission (the “SEC”). Accordingly, the unaudited condensed consolidated financial statements do not include all information and disclosure required by U.S. GAAP for annual financial statements. The December 31, 2017 Condensed Consolidated Balance Sheet information contained in this Quarterly Report on Form 10-Q was derived from the 2017 audited consolidated financial statements. The unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements, including the notes thereto, included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2017 . In the opinion of management, all adjustments (all of which are of a normal recurring nature) that are necessary for a fair statement are reflected in the unaudited condensed consolidated financial statements.
Reclassifications	Reclassifications Certain reclassifications have been made to prior year amounts to conform with current year classifications.
Recently Adopted and Recently Issued Accounting Standards	Recently Adopted and Recently Issued Accounting Standards The following accounting standards have been adopted in 2018: On January 1, 2018, the Company adopted changes, with subsequent amendments, issued by the Financial Accounting Standards Board ("FASB") related to the recognition of revenue from contracts with customers. The changes clarify the principles for recognizing revenue and develop a common revenue standard. The core principle of the changes is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The adoption of these changes resulted in the following modifications to the Company's revenue recognition process: • Harsco Industrial Segment - The timing of revenue recognition for air-cooled heat exchanger sales, which the Company historically recognized upon the completion of the efforts associated with these arrangements, is now recognized over time with the impact of increasing revenue in earlier periods. This change also impacted the Company's Condensed Consolidated Balance Sheets by decreasing both Inventories and Advances on contracts; and creating a new caption and establishing a balance related to Contract assets. • Harsco Rail Segment - The timing of revenue recognition for certain railway track maintenance equipment sales, which the Company historically recognized upon the completion of the efforts associated with these arrangements, is now recognized over time with the impact of increasing revenue in earlier periods. This change also impacted the Company's Condensed Consolidated Balance Sheets by decreasing both Inventories and Advances on contracts; and creating a new caption and establishing a balance related to Contract assets. In addition, certain advance payments received from customers, which provide a significant benefit of financing and are expected to be outstanding longer than twelve months, are treated as significant financing components to the related transactions and the Company will increase the overall transaction price with a corresponding increase in interest expense. Additionally, the Company's disclosure related to revenue recognition has been expanded in accordance with the FASB changes. Please refer to Note 14, Revenue Recognition for additional information. The Company chose to implement the impact of the FASB changes utilizing the modified retrospective transition method, using the following practical expedients: • The Company has elected to apply the changes only to revenue arrangements that were not completed as of January 1, 2018; and • The Company has elected to reflect the aggregate effect of all contract modifications that occurred prior to the beginning of the earliest reported period when (i) identifying the satisfied and unsatisfied performance obligations; (ii) determining the transaction price; and (iii) allocating the transaction price to the satisfied and unsatisfied performance obligations. Comparative information has not been restated and continues to be reported under U.S. GAAP in effect for those periods. The cumulative effect of the changes made to the Condensed Consolidated Balance Sheet at January 1, 2018 was as follows: (In thousands) Balance at December 31, 2017 Impact of Adoption Balance at January 1, 2018 ASSETS Current assets: Trade accounts receivable, net $ 288,034 $ 532 $ 288,566 Inventories 178,293 (59,793 ) 118,500 Current portion of contract assets — 18,248 18,248 Other current assets 39,332 179 39,511 Total current assets 592,092 (40,834 ) 551,258 Contract assets — 3,566 3,566 Other assets 15,263 1,337 16,600 Total assets 1,578,685 (35,931 ) 1,542,754 LIABILITIES Current liabilities: Current portion of advances on contracts 117,958 (78,507 ) 39,451 Other current liabilities 133,368 13,995 147,363 Total current liabilities 474,128 (64,512 ) 409,616 Advances on contracts — 24,564 24,564 Other liabilities 40,846 1,580 42,426 Total liabilities 1,363,520 (38,368 ) 1,325,152 HARSCO CORPORATION STOCKHOLDERS' EQUITY Accumulated other comprehensive loss (546,582 ) (1,520 ) (548,102 ) Retained earnings 1,157,801 3,957 1,161,758 Total Harsco Corporation stockholders' equity 170,451 2,437 172,888 Total equity 215,165 2,437 217,602 Total liabilities and equity 1,578,685 (35,931 ) 1,542,754 The impact of modifying the Company's Condensed Consolidated Balance Sheet at September 30, 2018 is as follows: September 30, 2018 (In thousands) As Reported Impact of Adoption As Reported - Less Impact of Adoption ASSETS Current assets: Trade accounts receivable, net $ 304,165 $ (535 ) $ 303,630 Inventories 137,768 91,285 229,053 Current portion of contract assets 27,870 (27,870 ) — Other current assets 42,068 (157 ) 41,911 Total current assets 631,578 62,723 694,301 Contract assets 3,566 (3,566 ) — Deferred income tax assets 39,824 1,874 41,698 Other assets 21,002 (1,040 ) 19,962 Total assets 1,660,417 59,991 1,720,408 September 30, 2018 (In thousands) As Reported Impact of Adoption As Reported - Less Impact of Adoption LIABILITIES Current liabilities: Current portion of advances on contracts 43,682 83,121 126,803 Other current liabilities 121,887 (8,608 ) 113,279 Total current liabilities 431,074 74,513 505,587 Advances on contracts 10,322 (10,322 ) — Other liabilities 54,273 (216 ) 54,057 Total liabilities 1,356,026 63,975 1,420,001 HARSCO CORPORATION STOCKHOLDERS' EQUITY Accumulated other comprehensive loss (555,291 ) 1,679 (553,612 ) Retained earnings 1,252,840 (5,671 ) 1,247,169 Total Harsco Corporation stockholders' equity 261,551 (3,992 ) 257,559 Noncontrolling interests 42,840 8 42,848 Total equity 304,391 (3,984 ) 300,407 Total liabilities and equity 1,660,417 59,991 1,720,408 The impact of modifying the Company's Condensed Consolidated Statements of Operations for the three and nine months ended September 30, 2018 are as follows: Three Months Ended September 30, 2018 (In thousands, except per share amounts) As Reported Impact of Adoption As Reported - Less Impact of Adoption Revenues from continuing operations: Services revenues $ 250,890 $ 512 $ 251,402 Product revenues 194,585 (15,411 ) 179,174 Total revenues 445,475 (14,899 ) 430,576 Costs and expenses from continuing operations: Costs of services sold 194,459 1,273 195,732 Costs of products sold 132,262 (11,979 ) 120,283 Selling, general and administrative costs 59,297 66 59,363 Total costs and expenses 388,366 (10,640 ) 377,726 Operating income from continuing operations 57,109 (4,259 ) 52,850 Interest expense (9,665 ) 550 (9,115 ) Income from continuing operations before income taxes 48,821 (3,709 ) 45,112 Income tax (expense) benefit (13,833 ) 932 (12,901 ) Income from continuing operations 34,988 (2,777 ) 32,211 Net income 34,651 (2,777 ) 31,874 Less: Net income attributable to noncontrolling interests (1,804 ) (10 ) (1,814 ) Net income attributable to Harsco Corporation 32,847 (2,787 ) 30,060 Amounts attributable to Harsco Corporation common stockholders: Income from continuing operations, net of tax 33,184 (2,787 ) 30,397 Net income attributable to Harsco Corporation common stockholders 32,847 (2,787 ) 30,060 Basic earnings per share attributable to Harsco Corporation common stockholders: Continuing operations 0.41 (0.03 ) 0.38 Basic earnings per share attributable to Harsco Corporation common stockholders 0.41 (0.03 ) 0.37 Diluted earnings per share attributable to Harsco Corporation common stockholders: Continuing operations 0.40 (0.03 ) 0.36 Diluted earnings per share attributable to Harsco Corporation common stockholders 0.39 (0.03 ) 0.36 Nine Months Ended September 30, 2018 (In thousands, except per share amounts) As Reported Impact of Adoption As Reported - Less Impact of Adoption Revenues from continuing operations: Services revenues $ 763,815 $ 4,182 $ 767,997 Product revenues 521,670 (34,269 ) 487,401 Total revenues 1,285,485 (30,087 ) 1,255,398 Costs and expenses from continuing operations: Costs of services sold 589,738 3,980 593,718 Costs of products sold 367,218 (30,091 ) 337,127 Selling, general and administrative costs 175,307 103 175,410 Total costs and expenses 1,138,210 (26,008 ) 1,112,202 Operating income from continuing operations 147,275 (4,079 ) 143,196 Interest expense (29,241 ) 1,453 (27,788 ) Income from continuing operations before income taxes 121,195 (2,626 ) 118,569 Income tax (expense) benefit (24,043 ) 919 (23,124 ) Income from continuing operations 97,152 (1,707 ) 95,445 Net income 96,939 (1,707 ) 95,232 Less: Net income attributable to noncontrolling interests (5,795 ) (8 ) (5,803 ) Net income attributable to Harsco Corporation 91,144 (1,715 ) 89,429 Amounts attributable to Harsco Corporation common stockholders: Income from continuing operations, net of tax 91,357 (1,715 ) 89,642 Net income attributable to Harsco Corporation common stockholders 91,144 (1,715 ) 89,429 Basic earnings per share attributable to Harsco Corporation common stockholders: Continuing operations 1.13 (0.02 ) 1.11 Basic earnings per share attributable to Harsco Corporation common stockholders 1.13 (0.02 ) 1.11 Diluted earnings per share attributable to Harsco Corporation common stockholders: Continuing operations 1.09 (0.02 ) 1.07 Diluted earnings per share attributable to Harsco Corporation common stockholders 1.09 (0.02 ) 1.07 The impact of modifying the Company's Condensed Consolidated Statements of Cash Flows for the nine months ended September 30, 2018 is as follows: Nine Months Ended September 30, 2018 (In thousands) As Reported Impact of Adoption As Reported - Less Impact of Adoption Cash flows from operating activities: Net income $ 96,939 $ (1,707 ) $ 95,232 Adjustments to reconcile net income to net cash used by operating activities: Deferred income tax expense (benefit) 1,996 (919 ) 1,077 Changes in assets and liabilities: Accounts receivable (29,022 ) 8 (29,014 ) Inventories (18,852 ) (34,923 ) (53,775 ) Contract assets (10,427 ) 10,427 — Advances on contracts (12,339 ) 21,794 9,455 Other assets and liabilities (14,164 ) 5,320 (8,844 ) Net cash used by operating activities 95,014 — 95,014 On January 1, 2018, the Company adopted changes issued by the FASB related to how employers that sponsor defined benefit pension plans and other postretirement plans present the net periodic pension cost ("NPPC") in the statement of operations. Employers are required to report the service cost component in the same line item or items as other compensation costs arising from services rendered by the pertinent employees during the period. Other components of NPPC are required to be presented in the statement of operations separately from the service cost component and outside of the subtotal of income from operations. The changes also allow only the service cost component to be eligible for capitalization. The adoption of these changes resulted in the Company reclassifying $0.7 million and $2.1 million of NPPC expense for the three and nine months ended September 30, 2017 , respectively, from the captions Cost of services sold; Cost of products sold; and Selling, general and administrative expenses to the new caption, Defined benefit pension income (expense) in the Company's Condensed Consolidated Statements of Operations. On January 1, 2018, the Company adopted changes issued by the FASB clarifying when revisions to the terms or conditions of a share-based payment award require an entity to apply modification accounting. The changes require modification accounting only in circumstances when the terms or conditions result in changes to the fair value, vesting conditions or classification of the award as an equity instrument or a liability. The adoption of these changes did not have an impact on the Company's condensed consolidated financial statements. On January 1, 2018, the Company adopted changes issued by FASB which eliminate the requirement to defer the recognition of current and deferred income taxes for an intra-entity asset transfer until the asset has been sold to an outside party. Under the new guidance, an entity should recognize the income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs. The changes resulted in an adjustment to opening retained earnings of less than $0.1 million . The following accounting standards have been issued and become effective for the Company at a future date: In February 2016, the FASB issued changes, with subsequent amendments, in accounting for leases, which become effective for the Company on January 1, 2019. The changes introduce a lessee model that brings most leases onto the balance sheet, which will result in an increase in lease-related assets and liabilities. The changes also align many of the underlying principles of the new lessor model with those in the FASB’s new revenue recognition standard. Furthermore, the changes address other concerns related to the current lease model such as eliminating the requirement in current guidance for an entity to use bright-line tests in determining lease classification. The changes also require lessors to increase the transparency of their exposure to changes in value of their residual assets and how they manage that exposure. The Company has completed an assessment of existing leasing agreements and is in the process of quantifying the impact on the Company’s consolidated financial statements. The Company has elected to adopt these changes on a modified retrospective basis and the practical expedients allowing for adoption on a prospective basis. In addition, the Company is in the process of identifying changes to current business processes and internal controls to support the reporting and disclosure requirements of the new standard. In January 2017, the FASB issued changes that remove the second step of the annual goodwill impairment test, which requires a hypothetical purchase price allocation. The changes provide that the amount of goodwill impairment will be equal to the amount by which a reporting unit’s carrying value exceeds its fair value, not to exceed the carrying amount of goodwill. All other goodwill impairment guidance remains largely unchanged. The same one-step impairment test will be applied to goodwill at all reporting units, even those with zero or negative carrying amounts. Entities will be required to disclose the amount of goodwill at reporting units with zero or negative carrying amounts. The changes become effective for the Company on January 1, 2020. Management has determined that these changes will not have a material impact on the Company's condensed consolidated financial statements. However, should the Company be required to record a goodwill impairment charge in future periods, the amount recorded may differ compared to any amounts that might be recorded under current practice. In August 2017, the FASB issued changes which expand and refine hedge accounting for both financial and non-financial risk components, aligns the recognition and presentation of the effects of hedging instruments and hedged items in the financial statements and includes certain targeted improvements to ease the application of current guidance related to the assessment of hedge effectiveness. The amendments in this update should be applied to hedging relationships existing on the date of adoption, which includes a cumulative-effect adjustment to eliminate any ineffectiveness recorded to accumulated other comprehensive income or loss with a corresponding adjustment to the opening balance of retained earnings as of the beginning of the fiscal year in which adoption occurred. Presentation and disclosure amendments are required to be applied prospectively. The changes become effective for the Company on January 1, 2019. Management is currently evaluating the impact of these changes on its condensed consolidated financial statements. In February 2018, the FASB issued changes which allow entities to reclassify stranded income tax effects resulting from the Tax Cuts and Jobs Act (the “Act”) from accumulated other comprehensive income to retained earnings in their consolidated financial statements. Under the Act, deferred taxes were adjusted to reflect the reduction of the historical corporate income tax rate to the newly enacted corporate income tax rate, which left the tax effects on items within accumulated other comprehensive income stranded at historical tax rates. The changes become effective for the Company on January 1, 2019. The Company had approximately $21 million of stranded income tax effects in accumulated other comprehensive income at December 31, 2017 resulting from the Act which the Company plans to reclassify upon initial adoption of these changes. In August 2018, the FASB issued changes which modify the disclosure requirements for fair value measurements. The amendments in this update remove the requirement to disclose the amount of, and reasons for, transfers between Level 1 and Level 2 of the fair value hierarchy; the policy for timing of transfers between levels; and the valuation processes for Level 3 fair value measurements. The changes require disclosure of changes in unrealized gains and losses for the period included in other comprehensive income (loss) for recurring Level 3 fair value measurements held at the end of the reporting period and the range and weighted average of significant unobservable inputs used to develop Level 3 fair value measurements. The changes become effective for the Company on January 1, 2020. Management is currently evaluating the impact of these changes on its condensed consolidated financial statements. In August 2018, the FASB issued changes which modify the disclosure requirements for employers that sponsor defined benefit pension or other post-retirement plans. The changes remove the requirements to disclose: amounts in accumulated other comprehensive income (loss) expected to be recognized as components of net periodic benefit cost over the next fiscal year; the amount and timing of plan assets expected to be returned to the employer; and the effects of a one-percentage point change in assumed health care cost trend rates. The update also requires disclosure of an explanation of the reasons for significant gains and losses related to changes in the benefit obligation for the period. The changes become effective for the Company on January 1, 2021. Management is currently evaluating the impact of these changes on its condensed consolidated financial statements.

Recently Adopted and Recently_2

Recently Adopted and Recently Issued Accounting Standards (Tables)	9 Months Ended
	Sep. 30, 2018
Accounting Changes and Error Corrections [Abstract]
Schedule of New Accounting Pronouncements and Changes in Accounting Principles	The cumulative effect of the changes made to the Condensed Consolidated Balance Sheet at January 1, 2018 was as follows: (In thousands) Balance at December 31, 2017 Impact of Adoption Balance at January 1, 2018 ASSETS Current assets: Trade accounts receivable, net $ 288,034 $ 532 $ 288,566 Inventories 178,293 (59,793 ) 118,500 Current portion of contract assets — 18,248 18,248 Other current assets 39,332 179 39,511 Total current assets 592,092 (40,834 ) 551,258 Contract assets — 3,566 3,566 Other assets 15,263 1,337 16,600 Total assets 1,578,685 (35,931 ) 1,542,754 LIABILITIES Current liabilities: Current portion of advances on contracts 117,958 (78,507 ) 39,451 Other current liabilities 133,368 13,995 147,363 Total current liabilities 474,128 (64,512 ) 409,616 Advances on contracts — 24,564 24,564 Other liabilities 40,846 1,580 42,426 Total liabilities 1,363,520 (38,368 ) 1,325,152 HARSCO CORPORATION STOCKHOLDERS' EQUITY Accumulated other comprehensive loss (546,582 ) (1,520 ) (548,102 ) Retained earnings 1,157,801 3,957 1,161,758 Total Harsco Corporation stockholders' equity 170,451 2,437 172,888 Total equity 215,165 2,437 217,602 Total liabilities and equity 1,578,685 (35,931 ) 1,542,754 The impact of modifying the Company's Condensed Consolidated Balance Sheet at September 30, 2018 is as follows: September 30, 2018 (In thousands) As Reported Impact of Adoption As Reported - Less Impact of Adoption ASSETS Current assets: Trade accounts receivable, net $ 304,165 $ (535 ) $ 303,630 Inventories 137,768 91,285 229,053 Current portion of contract assets 27,870 (27,870 ) — Other current assets 42,068 (157 ) 41,911 Total current assets 631,578 62,723 694,301 Contract assets 3,566 (3,566 ) — Deferred income tax assets 39,824 1,874 41,698 Other assets 21,002 (1,040 ) 19,962 Total assets 1,660,417 59,991 1,720,408 September 30, 2018 (In thousands) As Reported Impact of Adoption As Reported - Less Impact of Adoption LIABILITIES Current liabilities: Current portion of advances on contracts 43,682 83,121 126,803 Other current liabilities 121,887 (8,608 ) 113,279 Total current liabilities 431,074 74,513 505,587 Advances on contracts 10,322 (10,322 ) — Other liabilities 54,273 (216 ) 54,057 Total liabilities 1,356,026 63,975 1,420,001 HARSCO CORPORATION STOCKHOLDERS' EQUITY Accumulated other comprehensive loss (555,291 ) 1,679 (553,612 ) Retained earnings 1,252,840 (5,671 ) 1,247,169 Total Harsco Corporation stockholders' equity 261,551 (3,992 ) 257,559 Noncontrolling interests 42,840 8 42,848 Total equity 304,391 (3,984 ) 300,407 Total liabilities and equity 1,660,417 59,991 1,720,408 The impact of modifying the Company's Condensed Consolidated Statements of Operations for the three and nine months ended September 30, 2018 are as follows: Three Months Ended September 30, 2018 (In thousands, except per share amounts) As Reported Impact of Adoption As Reported - Less Impact of Adoption Revenues from continuing operations: Services revenues $ 250,890 $ 512 $ 251,402 Product revenues 194,585 (15,411 ) 179,174 Total revenues 445,475 (14,899 ) 430,576 Costs and expenses from continuing operations: Costs of services sold 194,459 1,273 195,732 Costs of products sold 132,262 (11,979 ) 120,283 Selling, general and administrative costs 59,297 66 59,363 Total costs and expenses 388,366 (10,640 ) 377,726 Operating income from continuing operations 57,109 (4,259 ) 52,850 Interest expense (9,665 ) 550 (9,115 ) Income from continuing operations before income taxes 48,821 (3,709 ) 45,112 Income tax (expense) benefit (13,833 ) 932 (12,901 ) Income from continuing operations 34,988 (2,777 ) 32,211 Net income 34,651 (2,777 ) 31,874 Less: Net income attributable to noncontrolling interests (1,804 ) (10 ) (1,814 ) Net income attributable to Harsco Corporation 32,847 (2,787 ) 30,060 Amounts attributable to Harsco Corporation common stockholders: Income from continuing operations, net of tax 33,184 (2,787 ) 30,397 Net income attributable to Harsco Corporation common stockholders 32,847 (2,787 ) 30,060 Basic earnings per share attributable to Harsco Corporation common stockholders: Continuing operations 0.41 (0.03 ) 0.38 Basic earnings per share attributable to Harsco Corporation common stockholders 0.41 (0.03 ) 0.37 Diluted earnings per share attributable to Harsco Corporation common stockholders: Continuing operations 0.40 (0.03 ) 0.36 Diluted earnings per share attributable to Harsco Corporation common stockholders 0.39 (0.03 ) 0.36 Nine Months Ended September 30, 2018 (In thousands, except per share amounts) As Reported Impact of Adoption As Reported - Less Impact of Adoption Revenues from continuing operations: Services revenues $ 763,815 $ 4,182 $ 767,997 Product revenues 521,670 (34,269 ) 487,401 Total revenues 1,285,485 (30,087 ) 1,255,398 Costs and expenses from continuing operations: Costs of services sold 589,738 3,980 593,718 Costs of products sold 367,218 (30,091 ) 337,127 Selling, general and administrative costs 175,307 103 175,410 Total costs and expenses 1,138,210 (26,008 ) 1,112,202 Operating income from continuing operations 147,275 (4,079 ) 143,196 Interest expense (29,241 ) 1,453 (27,788 ) Income from continuing operations before income taxes 121,195 (2,626 ) 118,569 Income tax (expense) benefit (24,043 ) 919 (23,124 ) Income from continuing operations 97,152 (1,707 ) 95,445 Net income 96,939 (1,707 ) 95,232 Less: Net income attributable to noncontrolling interests (5,795 ) (8 ) (5,803 ) Net income attributable to Harsco Corporation 91,144 (1,715 ) 89,429 Amounts attributable to Harsco Corporation common stockholders: Income from continuing operations, net of tax 91,357 (1,715 ) 89,642 Net income attributable to Harsco Corporation common stockholders 91,144 (1,715 ) 89,429 Basic earnings per share attributable to Harsco Corporation common stockholders: Continuing operations 1.13 (0.02 ) 1.11 Basic earnings per share attributable to Harsco Corporation common stockholders 1.13 (0.02 ) 1.11 Diluted earnings per share attributable to Harsco Corporation common stockholders: Continuing operations 1.09 (0.02 ) 1.07 Diluted earnings per share attributable to Harsco Corporation common stockholders 1.09 (0.02 ) 1.07 The impact of modifying the Company's Condensed Consolidated Statements of Cash Flows for the nine months ended September 30, 2018 is as follows: Nine Months Ended September 30, 2018 (In thousands) As Reported Impact of Adoption As Reported - Less Impact of Adoption Cash flows from operating activities: Net income $ 96,939 $ (1,707 ) $ 95,232 Adjustments to reconcile net income to net cash used by operating activities: Deferred income tax expense (benefit) 1,996 (919 ) 1,077 Changes in assets and liabilities: Accounts receivable (29,022 ) 8 (29,014 ) Inventories (18,852 ) (34,923 ) (53,775 ) Contract assets (10,427 ) 10,427 — Advances on contracts (12,339 ) 21,794 9,455 Other assets and liabilities (14,164 ) 5,320 (8,844 ) Net cash used by operating activities 95,014 — 95,014

Acquisitions (Tables)

Acquisitions (Tables)	9 Months Ended
	Sep. 30, 2018
Business Combinations [Abstract]
Summary of assets acquired and liabilities assumed	The fair value recorded for the assets acquired and liabilities assumed for Altek is as follows: Preliminary Valuation (In millions) June 30 2018 Measurement Period Adjustments (a) September 30 Cash and cash equivalents $ 1.7 $ — $ 1.7 Net working capital (1.5 ) 0.2 (1.3 ) Property, plant and equipment 3.3 — 3.3 Intangible assets 52.5 0.2 52.7 Goodwill 20.9 5.8 26.7 Net deferred tax liabilities (8.5 ) — (8.5 ) Other liabilities (0.3 ) — (0.3 ) Total identifiable net assets of Altek $ 68.1 $ 6.2 $ 74.3
Summary of intangible assets and amortization periods	The following table details the preliminary valuation of identifiable intangible assets and amortization periods for Altek: Amortization Period Preliminary Valuation (Dollars in millions) June 30 2018 Measurement Period Adjustments (a) September 30 Customer related 14.2 years $ 11.5 $ 0.1 $ 11.6 Technology related 10.3 years 36.5 0.1 36.6 Trade names 15.0 years 4.5 — 4.5 Total identifiable intangible assets of Altek $ 52.5 $ 0.2 $ 52.7 (a) The measurement period adjustments did not have a material impact on the Company's previously reported operating results.
Summary of changes in fair value of contingent consideration	The following table reflects the changes in the fair value of contingent consideration: (In thousands) Contingent Consideration Balance, June 30, 2018 $ 10,097 Measurement period adjustment (b) 6,177 Fair value adjustment (c) 412 Foreign currency translation (c) (298 ) Balance, September 30, 2018 $ 16,388 (b) Measurement period adjustment was recorded to goodwill on the Condensed Consolidated Balance Sheet.

Accounts Receivable and Inven_2

Accounts Receivable and Inventories (Tables)	9 Months Ended
	Sep. 30, 2018
Accounts Receivable And Inventories
Schedule of accounts receivable	Accounts receivable consist of the following: (In thousands) September 30 December 31 Trade accounts receivable $ 308,278 $ 292,765 Less: Allowance for doubtful accounts (4,113 ) (4,731 ) Trade accounts receivable, net $ 304,165 $ 288,034 Other receivables (a) (b) $ 55,156 $ 20,224
Schedule of provision for doubtful accounts related to trade accounts receivable	The provision (benefit) for doubtful accounts related to trade accounts receivable was as follows: Three Months Ended Nine Months Ended September 30 September 30 (In thousands) 2018 2017 2018 2017 Provision (benefit) for doubtful accounts related to trade accounts receivable $ (26 ) $ 4,087 $ (182 ) $ 5,262
Schedule of inventories	Inventories consist of the following: (In thousands) September 30 December 31 Finished goods $ 19,957 $ 26,415 Work-in-process 22,175 24,367 Contracts-in-process (c) — 45,599 Raw materials and purchased parts 72,935 58,943 Stores and supplies 22,701 22,969 Total inventories $ 137,768 $ 178,293
Schedule of contracts-in-process	Contracts-in-process consist of the following: (In thousands) December 31 Contract costs accumulated to date $ 73,740 Estimated forward loss provisions for contracts-in-process (d) (28,141 ) Contracts-in-process (c) (e) $ 45,599 (c) The Company has adopted the new revenue recognition standard utilizing the modified retrospective transition method, including use of practical expedients. Amounts previously reported as Contracts-in-progress have been recognized through the related cumulative catch-up adjustment. See Note 2, Recently Adopted and Recently Issued Accounting Standards for additional information. (d) For periods prior to January 1, 2018, to the extent that the estimated forward loss provision exceeds accumulated contract costs it is included in the caption Other current liabilities on the Condensed Consolidated Balance Sheets and amounted to $3.0 million at December 31, 2017 . (e) At December 31, 2017 , the Company had $97.9 million of net customer advances related to SBB contracts. These amounts are included in the caption Current portion of advances on contracts on the Condensed Consolidated Balance Sheets.

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	9 Months Ended
	Sep. 30, 2018
Property, Plant and Equipment [Abstract]
Schedule of property, plant and equipment	Property, plant and equipment consists of the following: (In thousands) September 30 December 31 Land $ 10,874 $ 10,840 Land improvements 15,874 14,996 Buildings and improvements 192,011 198,582 Machinery and equipment 1,554,559 1,599,713 Uncompleted construction 30,608 24,387 Gross property, plant and equipment 1,803,926 1,848,518 Less: Accumulated depreciation (1,343,428 ) (1,368,771 ) Property, plant and equipment, net $ 460,498 $ 479,747

Goodwill and Other Intangible_2

Goodwill and Other Intangible Assets (Tables)	9 Months Ended
	Sep. 30, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of changes in carrying amounts of goodwill by segment	The following table reflects the changes in carrying amounts of goodwill by segment for the nine months ended September 30, 2018 : (In thousands) Harsco Metals & Minerals Segment Harsco Industrial Segment Harsco Rail Segment Consolidated Totals Balance at December 31, 2017 $ 381,893 $ 6,839 $ 13,026 $ 401,758 Changes to goodwill 26,737 (a) — — 26,737 Foreign currency translation (8,144 ) — — (8,144 ) Balance at September 30, 2018 $ 400,486 $ 6,839 $ 13,026 $ 420,351
Schedule of intangible assets by class	Intangible assets included in the caption, Intangible assets, net, on the Condensed Consolidated Balance Sheets consist of the following: September 30, 2018 December 31, 2017 (In thousands) Gross Carrying Amount Accumulated Amortization Gross Carrying Amount Accumulated Amortization Customer related (b) $ 137,498 $ 98,834 $ 153,014 $ 121,385 Patents 2,590 2,495 5,825 5,700 Technology related (b) 36,666 1,851 26,131 26,131 Trade names (b) 9,311 1,754 8,317 4,845 Other 5,856 3,389 8,875 5,850 Total $ 191,921 $ 108,323 $ 202,162 $ 163,911
Schedule of amortization expense	Amortization expense for intangible assets was as follows: Three Months Ended Nine Months Ended September 30 September 30 (In thousands) 2018 2017 2018 2017 Amortization expense for intangible assets $ 2,395 $ 1,269 $ 5,326 $ 3,868
Schedule of estimated amortization expense	The estimated amortization expense for the next five fiscal years based on current intangible assets is as follows: (In thousands) 2018 2019 2020 2021 2022 Estimated amortization expense (c) $ 7,900 $ 9,750 $ 9,250 $ 8,800 $ 8,500

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	9 Months Ended
	Sep. 30, 2018
Retirement Benefits [Abstract]
Schedule of net benefit costs	Three Months Ended September 30 Defined Benefit Pension Plans Net Periodic Pension Cost (Benefit) U.S. Plans International Plans (In thousands) 2018 2017 2018 2017 Service costs $ 10 $ 10 $ 401 $ 426 Interest costs 2,391 2,469 5,498 5,843 Expected return on plan assets (3,017 ) (2,620 ) (10,820 ) (10,632 ) Recognized prior service costs — 8 (37 ) 48 Recognized loss 1,302 1,425 3,737 4,130 Defined benefit pension plans net periodic pension cost (benefit) $ 686 $ 1,292 $ (1,221 ) $ (185 ) Nine Months Ended Sept 30 Defined Benefit Pension Plans Net Periodic Pension Cost (Benefit) U.S. Plans International Plans (In thousands) 2018 2017 2018 2017 Service costs $ 31 $ 32 $ 1,195 $ 1,243 Interest costs 7,172 7,408 16,612 17,349 Expected return on plan assets (9,051 ) (7,863 ) (32,661 ) (31,571 ) Recognized prior service costs — 24 (113 ) 139 Recognized loss 3,906 4,276 11,267 12,260 Settlement/curtailment losses 166 — — — Defined benefit pension plans net periodic pension cost (benefit) $ 2,224 $ 3,877 $ (3,700 ) $ (580 )
Schedule of contributions to pension plans	Three Months Ended Nine Months Ended Company Contributions September 30 September 30 (In thousands) 2018 2017 2018 2017 Defined benefit pension plans (U.S.) $ 5,958 $ 4,112 $ 9,309 $ 5,054 Defined benefit pension plans (International) 3,219 3,038 16,192 14,338 Multiemployer pension plans 492 498 1,512 1,481 Defined contribution pension plans 2,306 3,278 7,888 8,306

Reconciliation of Basic and D_2

Reconciliation of Basic and Diluted Shares (Tables)	9 Months Ended
	Sep. 30, 2018
Earnings Per Share [Abstract]
Reconciliation of basic and diluted shares	Three Months Ended Nine Months Ended September 30 September 30 (In thousands, except per share amounts) 2018 2017 2018 2017 Income from continuing operations attributable to Harsco Corporation common stockholders $ 33,184 $ 13,669 $ 91,357 $ 41,571 Weighted-average shares outstanding - basic 80,950 80,637 80,821 80,519 Dilutive effect of stock-based compensation 2,929 2,499 2,869 2,234 Weighted-average shares outstanding - diluted 83,879 83,136 83,690 82,753 Earnings from continuing operations per common share, attributable to Harsco Corporation common stockholders: Basic $ 0.41 $ 0.17 $ 1.13 $ 0.52 Diluted $ 0.40 $ 0.16 $ 1.09 $ 0.50
Schedule of antidilutive securities excluded from computation of earnings per share	The following average outstanding stock-based compensation units were not included in the computation of diluted earnings per share because the effect was antidilutive: Three Months Ended Nine Months Ended September 30 September 30 (In thousands) 2018 2017 2018 2017 Stock options — 55 — 55 Stock appreciation rights 75 526 349 918 Performance share units — — — 212

Derivative Instruments, Hedgi_2

Derivative Instruments, Hedging Activities and Fair Value (Tables)	9 Months Ended
	Sep. 30, 2018
Derivative Instruments, Hedging Activities And Fair Value Disclosure [Abstract]
Schedule of fair value of outstanding derivative contracts	The fair value of outstanding derivative contracts recorded as assets and liabilities on the Condensed Consolidated Balance Sheets was as follows: (In thousands) Balance Sheet Location Fair Value of Derivatives Designated as Hedging Instruments Fair Value of Derivatives Not Designated as Hedging Instruments Total Fair Value September 30, 2018 Asset derivatives (Level 2): Foreign currency exchange forward contracts Other current assets $ 2,209 $ 7,742 $ 9,951 Interest rate swaps Other current assets 1,900 — 1,900 Interest rate swaps Other assets 3,453 — 3,453 Total $ 7,562 $ 7,742 $ 15,304 Liability derivatives (Level 2): Foreign currency exchange forward contracts Other current liabilities $ 109 $ 1,583 $ 1,692 Interest rate swaps Other liabilities 31 — 31 Total $ 140 $ 1,583 $ 1,723 (In thousands) Balance Sheet Location Fair Value of Derivatives Designated as Hedging Instruments Fair Value of Derivatives Not Designated as Hedging Instruments Total Fair Value December 31, 2017 Asset derivatives (Level 2): Foreign currency exchange forward contracts Other current assets $ 2,329 $ 2,915 $ 5,244 Interest rate swaps Other current assets 464 — 464 Interest rate swaps Other assets 170 — $ 170 Total $ 2,963 $ 2,915 $ 5,878 Liability derivatives (Level 2): Foreign currency exchange forward contracts Other current liabilities $ 153 $ 6,970 $ 7,123 Interest rate swaps Other liabilities 1,368 — 1,368 Total $ 1,521 $ 6,970 $ 8,491
Schedule of effect of derivative instruments	The effect of derivative instruments in the Condensed Consolidated Statements of Operations and the Condensed Consolidated Statements of Comprehensive Income, was as follows: Derivatives Designated as Hedging Instruments (In thousands) Amount Recognized in Other Comprehensive Income (“OCI”) on Derivative - Effective Portion Location of Amount Reclassified from Accumulated OCI into Income - Effective Portion Amount Reclassified from Accumulated OCI into Income - Effective Portion or Equity Location of Amount Recognized in Income on Derivative - Ineffective Portion and Amount Excluded from Effectiveness Testing Amount Recognized in Income on Derivative - Ineffective Portion and Amount Excluded from Effectiveness Testing Three Months Ended September 30, 2018: Foreign currency exchange forward contracts $ (410 ) Product revenues $ (3 ) $ — Interest rate swaps 1,276 Interest expense (367 ) — Cross-currency interest rate swaps — (a) Interest expense 312 — $ 866 $ (58 ) $ — Three Months Ended September 30, 2017: Foreign currency exchange forward contracts $ 2,333 $ — $ — Interest rate swaps (335 ) — — Cross-currency interest rate swaps (72 ) (a) Interest Expense 252 Cost of services and products sold (103 ) $ 1,926 $ 252 $ (103 ) (In thousands) Amount Recognized in Other Comprehensive Income (“OCI”) on Derivative - Effective Portion Location of Amount Reclassified from Accumulated OCI into Income - Effective Portion Amount Reclassified from Accumulated OCI into Income - Effective Portion or Equity Location of Amount Recognized in Income on Derivative - Ineffective Portion and Amount Excluded from Effectiveness Testing Amount Recognized in Income on Derivative - Ineffective Portion and Amount Excluded from Effectiveness Testing Nine Months Ended September 30, 2018: Foreign currency forward exchange contracts $ 1,369 Product revenues / Cost of services and products sold $ (112 ) $ — Foreign currency forward exchange contracts — Retained earnings (b) (1,520 ) — Interest rate swaps 6,657 Interest expense (602 ) — Cross currency interest rate swaps — Interest expense 960 — $ 8,026 $ (1,274 ) $ — Nine Months Ended September 30, 2017: Foreign currency forward exchange contracts $ 3,096 Product revenues / Cost of services and products sold $ (185 ) $ — Interest rate swaps (2,878 ) — — Cross currency interest rate swaps (195 ) (a) Interest expense 745 Cost of services and products sold (420 ) $ 23 $ 560 $ (420 ) (a) Amounts represent changes in foreign currency translation related to balances in Accumulated other comprehensive loss. (b) The Company has adopted the new revenue recognition standard utilizing the modified retrospective transition method, including use of practical expedients. See Note 2, Recently Adopted and Recently Issued Accounting Standards for additional information. Derivatives Not Designated as Hedging Instruments Location of Gain (Loss) Recognized in Income on Derivative Amount of Gain (Loss) Recognized in Income on Derivative(c) (In thousands) 2018 2017 Three Months Ended September 30: Foreign currency exchange forward contracts Cost of services and products sold $ 3,194 $ (7,025 ) Nine Months Ended September 30: Foreign currency exchange forward contracts Cost of services and products sold $ 13,459 $ (18,764 ) (c) These gains (losses) offset amounts recognized in cost of services and products sold principally as a result of intercompany or third party foreign currency exposures.

Review of Operations by Segme_2

Review of Operations by Segment (Tables)	9 Months Ended
	Sep. 30, 2018
Segment Reporting [Abstract]
Schedule of operations by segment	Three Months Ended Nine Months Ended September 30 September 30 (In thousands) 2018 2017 2018 2017 Revenues From Continuing Operations Harsco Metals & Minerals $ 268,881 $ 255,163 $ 805,924 $ 761,503 Harsco Industrial 93,912 78,318 269,575 217,766 Harsco Rail 82,682 51,134 209,912 172,716 Corporate — 38 74 107 Total Revenues From Continuing Operations $ 445,475 $ 384,653 $ 1,285,485 $ 1,152,092 Three Months Ended Nine Months Ended September 30 September 30 (In thousands) 2018 2017 2018 2017 Operating Income (Loss) From Continuing Operations Harsco Metals & Minerals $ 29,338 $ 23,613 $ 92,734 $ 80,834 Harsco Industrial 13,959 12,954 40,550 25,088 Harsco Rail 19,000 4,391 29,570 18,800 Corporate (5,188 ) (6,329 ) (15,579 ) (18,337 ) Total Operating Income From Continuing Operations $ 57,109 $ 34,629 $ 147,275 $ 106,385 Depreciation and Amortization Harsco Metals & Minerals $ 29,007 $ 28,636 $ 86,724 $ 84,444 Harsco Industrial 1,971 1,826 5,708 5,509 Harsco Rail 1,063 1,094 3,166 3,156 Corporate 1,332 1,449 4,346 4,399 Total Depreciation and Amortization $ 33,373 $ 33,005 $ 99,944 $ 97,508 Capital Expenditures Harsco Metals & Minerals $ 29,870 $ 20,994 $ 79,469 $ 58,065 Harsco Industrial 1,891 1,678 5,894 3,226 Harsco Rail 2,748 462 5,266 1,765 Corporate 297 297 673 1,075 Total Capital Expenditures $ 34,806 $ 23,431 $ 91,302 $ 64,131
Reconciliation of segment operating income to income from continuing operations before income taxes and equity income	Reconciliation of Segment Operating Income to Income From Continuing Operations Before Income Taxes Three Months Ended Nine Months Ended September 30 September 30 (In thousands) 2018 2017 2018 2017 Segment operating income $ 62,297 $ 40,958 $ 162,854 $ 124,722 General Corporate expense (5,188 ) (6,329 ) (15,579 ) (18,337 ) Operating income from continuing operations 57,109 34,629 147,275 106,385 Interest income 574 610 1,649 1,615 Interest expense (9,665 ) (12,122 ) (29,241 ) (36,180 ) Defined benefit pension income (expense) 928 (680 ) 2,671 (2,054 ) Loss on early extinguishment of debt (125 ) — (1,159 ) — Income from continuing operations before income taxes $ 48,821 $ 22,437 $ 121,195 $ 69,766

Revenue Recognition (Tables)

Revenue Recognition (Tables)	9 Months Ended
	Sep. 30, 2018
Revenue from Contract with Customer [Abstract]
Summary of revenues by primary geographical markets	A summary of the Company's revenues by primary geographical markets as well as by key product and service groups is as follows: Three Months Ended September 30, 2018 (In thousands) Harsco Metals & Minerals Segment Harsco Industrial Segment Harsco Rail Segment Corporate Consolidated Totals Primary Geographical Markets (a) : North America $ 78,844 $ 88,524 $ 62,823 $ — $ 230,191 Western Europe 97,411 — 10,720 — 108,131 Latin America (b) 36,165 5,388 1,130 — 42,683 Asia-Pacific 36,846 — 8,009 — 44,855 Middle East and Africa 12,370 — — — 12,370 Eastern Europe 7,245 — — — 7,245 Total Revenues (c) $ 268,881 $ 93,912 $ 82,682 $ — $ 445,475 Key Product and Service Groups: On-site services and material logistics, product quality improvement and resource recovery for iron, steel and metals manufacturing; as well as value- added environmental solutions for industrial co-products $ 268,881 $ — $ — $ — $ 268,881 Railway track maintenance services and equipment — — 82,682 — 82,682 Air-cooled heat exchangers — 52,093 — — 52,093 Industrial grating and fencing products — 31,782 — — 31,782 Heat transfer products — 10,037 — — 10,037 Total Revenues (c) $ 268,881 $ 93,912 $ 82,682 $ — $ 445,475 Three Months Ended September 30, 2017 (In thousands) Harsco Metals & Minerals Segment Harsco Industrial Segment Harsco Rail Segment Corporate Consolidated Totals Primary Geographical Markets (a) : North America $ 70,325 $ 72,260 $ 36,112 $ 38 $ 178,735 Western Europe 89,481 — 10,495 — 99,976 Latin America (b) 41,656 5,026 737 — 47,419 Asia-Pacific 35,990 1,032 3,790 — 40,812 Middle East and Africa 10,849 — — — 10,849 Eastern Europe 6,862 — — — 6,862 Total Revenues (c) $ 255,163 $ 78,318 $ 51,134 $ 38 $ 384,653 Key Product and Service Groups: On-site services and material logistics, product quality improvement and resource recovery for iron, steel and metals manufacturing; as well as value- added environmental solutions for industrial co-products $ 255,163 $ — $ — $ — $ 255,163 Railway track maintenance services and equipment — — 51,134 — 51,134 Air-cooled heat exchangers — 38,248 — — 38,248 Industrial grating and fencing products — 29,659 — — 29,659 Heat transfer products — 10,411 — — 10,411 General Corporate — — — 38 38 Total Revenues (c) $ 255,163 $ 78,318 $ 51,134 $ 38 $ 384,653 Nine Months Ended September 30, 2018 (In thousands) Harsco Metals & Minerals Segment Harsco Industrial Segment Harsco Rail Segment Corporate Consolidated Totals Primary Geographical Markets (a) : North America $ 229,771 $ 254,556 $ 150,775 $ 74 $ 635,176 Western Europe 291,742 — 38,481 — 330,223 Latin America (b) 115,011 15,019 3,294 — 133,324 Asia-Pacific 110,855 — 17,362 — 128,217 Middle East and Africa 36,073 — — — 36,073 Eastern Europe 22,472 — — — 22,472 Total Revenues (c) $ 805,924 $ 269,575 $ 209,912 $ 74 $ 1,285,485 Key Product and Service Groups: On-site services and material logistics, product quality improvement and resource recovery for iron, steel and metals manufacturing; as well as value- added environmental solutions for industrial co-products $ 805,924 $ — $ — $ — $ 805,924 Railway track maintenance services and equipment — — 209,912 — 209,912 Air-cooled heat exchangers — 144,936 — — 144,936 Industrial grating and fencing products — 94,325 — — 94,325 Heat transfer products — 30,314 — — 30,314 General Corporate — — — 74 74 Total Revenues (c) $ 805,924 $ 269,575 $ 209,912 $ 74 $ 1,285,485 Nine Months Ended September 30, 2017 (In thousands) Harsco Metals & Minerals Segment Harsco Industrial Segment Harsco Rail Segment Corporate Consolidated Totals Primary Geographical Markets (a) : North America $ 208,317 $ 197,776 $ 130,010 $ 107 $ 536,210 Western Europe 278,717 — 26,866 — 305,583 Latin America (b) 119,434 16,916 1,991 — 138,341 Asia-Pacific 103,306 3,074 13,849 — 120,229 Middle East and Africa 31,358 — — — 31,358 Eastern Europe 20,371 — — — 20,371 Total Revenues (c) $ 761,503 $ 217,766 $ 172,716 $ 107 $ 1,152,092 Key Product and Service Groups: On-site services and material logistics, product quality improvement and resource recovery for iron, steel and metals manufacturing; as well as value- added environmental solutions for industrial co-products $ 761,503 $ — $ — $ — $ 761,503 Railway track maintenance services and equipment — — 172,716 — 172,716 Air-cooled heat exchangers — 102,483 — — 102,483 Industrial grating and fencing products — 86,952 — — 86,952 Heat transfer products — 28,331 — — 28,331 General Corporate — — — 107 107 Total Revenues (c) $ 761,503 $ 217,766 $ 172,716 $ 107 $ 1,152,092 (a) Revenues are attributed to individual countries based on the location of the facility generating the revenue. (b) Includes Mexico. (c)
Summary of contract assets and advances on contracts	The following table reflects Contract assets and Advances on contracts: (In thousands) September 30, 2018 December 31, 2017 Contract assets: Current portion of contract assets $ 27,870 $ — Contract assets 3,566 — Total contract assets $ 31,436 $ — Advances on contracts: Current portion of advances on contracts $ 43,682 $ 117,958 Advances on contracts 10,322 — Total advances on contracts $ 54,004 $ 117,958

Other (Income) Expenses, Net (T

Other (Income) Expenses, Net (Tables)	9 Months Ended
	Sep. 30, 2018
Other Income and Expenses [Abstract]
Schedule of other (income) expenses	The major components of this Condensed Consolidated Statements of Operations caption are as follows: Three Months Ended Nine Months Ended September 30 September 30 (In thousands) 2018 2017 2018 2017 Employee termination benefit costs $ 1,037 $ 2,536 $ 3,249 $ 4,947 Net gains (a) (1,262 ) (4,821 ) (2,359 ) (4,815 ) Other costs to exit activities 11 327 475 495 Impaired asset write-downs — 539 113 820 Contingent consideration adjustments 412 — 412 — Other 430 182 (320 ) 282 Other (income) expenses, net $ 628 $ (1,237 ) $ 1,570 $ 1,729 (a)

Components of Accumulated Oth_2

Components of Accumulated Other Comprehensive Loss (Tables)	9 Months Ended
	Sep. 30, 2018
Equity [Abstract]
Schedule of accumulated other comprehensive loss	The components of Accumulated other comprehensive loss, net of the effect of income taxes, and activity for the nine months ended September 30, 2017 and 2018 was as follows: Components of Accumulated Other Comprehensive Income (Loss) - Net of Tax (In thousands) Cumulative Foreign Exchange Translation Adjustments Effective Portion of Derivatives Designated as Hedging Instruments Cumulative Unrecognized Actuarial Losses on Pension Obligations Unrealized Gain (Loss) on Marketable Securities Total Balance at December 31, 2016 $ (144,534 ) $ (1,089 ) $ (461,094 ) $ (5 ) $ (606,722 ) Other comprehensive income (loss) before reclassifications 42,391 (a) 1,133 (b) (31,600 ) (a) 11 11,935 Amounts reclassified from accumulated other comprehensive loss, net of tax — 338 15,133 — 15,471 Total other comprehensive income (loss) 42,391 1,471 (16,467 ) 11 27,406 Other comprehensive loss attributable to noncontrolling interests (2,235 ) — — — (2,235 ) Other comprehensive income (loss) attributable to Harsco Corporation 40,156 1,471 (16,467 ) 11 25,171 Balance at September 30, 2017 $ (104,378 ) $ 382 $ (477,561 ) $ 6 $ (581,551 ) Components of Accumulated Other Comprehensive Income (Loss) - Net of Tax (In thousands) Cumulative Foreign Exchange Translation Adjustments Effective Portion of Derivatives Designated as Hedging Instruments Cumulative Unrecognized Actuarial Losses on Pension Obligations Unrealized Gain (Loss) on Marketable Securities Total Balance at December 31, 2017 $ (111,567 ) $ 808 $ (435,840 ) $ 17 $ (546,582 ) Adoption of new accounting standard (c) — (1,520 ) — — (1,520 ) Balance at January 1, 2018 (111,567 ) (712 ) (435,840 ) 17 (548,102 ) Other comprehensive income (loss) before reclassifications (40,157 ) (a) 6,055 (b) 9,970 (a) (19 ) (24,151 ) Amounts reclassified from accumulated other comprehensive loss, net of tax — 26 14,324 — 14,350 Total other comprehensive income (loss) (40,157 ) 6,081 24,294 (19 ) (9,801 ) Other comprehensive income attributable to noncontrolling interests 2,612 — — — 2,612 Other comprehensive income (loss) attributable to Harsco Corporation (37,545 ) 6,081 24,294 (19 ) (7,189 ) Balance at September 30, 2018 $ (149,112 ) $ 5,369 $ (411,546 ) $ (2 ) $ (555,291 ) (a) Principally foreign currency fluctuation. (b) Net change from periodic revaluations. (c) Represents the opening balance sheet adjustment to retained earnings related to the adoption of the revenue recognition standard adopted by the Company on January 1, 2018. See Note 2, Recently Adopted and Recently Issued Accounting Standards, for additional details.
Reclassification out of accumulated other comprehensive income	Amounts reclassified from accumulated other comprehensive loss are as follows: (In thousands) Three Months Ended Nine Months Ended Affected Caption in the Condensed Consolidated Statements of Operations September 30 September 30 September 30 September 30 Amortization of cash flow hedging instruments: Foreign currency exchange forward contracts $ (3 ) $ — $ (112 ) $ (189 ) Product revenues Foreign currency exchange forward contracts — — — 4 Cost of services and products sold Cross-currency interest rate swaps 312 252 960 745 Interest expense Interest rate swaps (367 ) — (602 ) — Interest expense Total before tax (58 ) 252 246 560 Tax expense (13 ) (99 ) (220 ) (222 ) Total reclassification of cash flow hedging instruments, net of tax $ (71 ) $ 153 $ 26 $ 338 Amortization of defined benefit pension items (d) : Recognized losses $ 5,039 $ 5,558 $ 15,173 $ 16,536 Defined benefit pension income (expense) Recognized prior-service costs (37 ) 56 (113 ) 163 Defined benefit pension income (expense) Settlement/curtailment losses — — 166 — Defined benefit pension income (expense) Total before tax 5,002 5,614 15,226 16,699 Tax benefit (289 ) (523 ) (902 ) (1,566 ) Total reclassification of defined benefit pension items, net of tax $ 4,713 $ 5,091 $ 14,324 $ 15,133 (d)

Recently Adopted and Recently_3

Recently Adopted and Recently Issued Accounting Standards - Condensed Consolidated Balance Sheet (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Jan. 01, 2018	Dec. 31, 2017	Sep. 30, 2017	Dec. 31, 2016
Current assets:
Trade accounts receivable, net	$ 304,165	$ 288,566	$ 288,034
Inventories	137,768	118,500	178,293
Current portion of contract assets	27,870	18,248	0
Other current assets	42,068	39,511	39,332
Total current assets	631,578	551,258	592,092
Contract assets	3,566	3,566	0
Deferred income tax assets	39,824		51,574
Other assets	21,002	16,600	15,263
Total assets	1,660,417	1,542,754	1,578,685
Current liabilities:
Current portion of advances on contracts	43,682	39,451	117,958
Other current liabilities	121,887	147,363	133,368
Total current liabilities	431,074	409,616	474,128
Advances on contracts	10,322	24,564	0
Other liabilities	54,273	42,426	40,846
Liabilities	1,356,026	1,325,152	1,363,520
HARSCO CORPORATION STOCKHOLDERS' EQUITY
Accumulated other comprehensive loss	(555,291)	(548,102)	(546,582)
Retained earnings	1,252,840	1,161,758	1,157,801
Stockholders' Equity Attributable to Parent	261,551	172,888	170,451
Stockholders' Equity Attributable to Noncontrolling Interest	42,840		44,714
Total equity	304,391	217,602	215,165	$ 210,018	$ 137,563
Total liabilities and equity	1,660,417	1,542,754	1,578,685
Calculated under Revenue Guidance in Effect before Topic 606 [Member]
Current assets:
Trade accounts receivable, net	303,630		288,034
Inventories	229,053		178,293
Current portion of contract assets	0		0
Other current assets	41,911		39,332
Total current assets	694,301		592,092
Contract assets	0		0
Deferred income tax assets	41,698
Other assets	19,962		15,263
Total assets	1,720,408		1,578,685
Current liabilities:
Current portion of advances on contracts	126,803		117,958
Other current liabilities	113,279		133,368
Total current liabilities	505,587		474,128
Advances on contracts	0		0
Other liabilities	54,057		40,846
Liabilities	1,420,001		1,363,520
HARSCO CORPORATION STOCKHOLDERS' EQUITY
Accumulated other comprehensive loss	(553,612)		(546,582)
Retained earnings	1,247,169		1,157,801
Stockholders' Equity Attributable to Parent	257,559		170,451
Stockholders' Equity Attributable to Noncontrolling Interest	42,848
Total equity	300,407		215,165
Total liabilities and equity	1,720,408		$ 1,578,685
Difference between Revenue Guidance in Effect before and after Topic 606 | Accounting Standards Update 2014-09
Current assets:
Trade accounts receivable, net	(535)	532
Inventories	91,285	(59,793)
Current portion of contract assets	(27,870)	18,248
Other current assets	(157)	179
Total current assets	62,723	(40,834)
Contract assets	(3,566)	3,566
Deferred income tax assets	1,874
Other assets	(1,040)	1,337
Total assets	59,991	(35,931)
Current liabilities:
Current portion of advances on contracts	83,121	(78,507)
Other current liabilities	(8,608)	13,995
Total current liabilities	74,513	(64,512)
Advances on contracts	(10,322)	24,564
Other liabilities	(216)	1,580
Liabilities	63,975	(38,368)
HARSCO CORPORATION STOCKHOLDERS' EQUITY
Accumulated other comprehensive loss	1,679	(1,520)
Retained earnings	(5,671)	3,957
Stockholders' Equity Attributable to Parent	(3,992)	2,437
Stockholders' Equity Attributable to Noncontrolling Interest	8
Total equity	(3,984)	2,437
Total liabilities and equity	$ 59,991	$ (35,931)

Recently Adopted and Recently_4

Recently Adopted and Recently Issued Accounting Standards - Condensed Consolidated Statements of Operations (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended				9 Months Ended
	Sep. 30, 2018		Sep. 30, 2017		Sep. 30, 2018	Sep. 30, 2017
Revenues from continuing operations:
Total revenues	$ 445,475		$ 384,653		$ 1,285,485	$ 1,152,092
Costs and expenses from continuing operations:
Selling, general and administrative costs	59,297		59,993		175,307	168,315
Total costs and expenses	388,366		350,024		1,138,210	1,045,707
Operating income from continuing operations	57,109		34,629		147,275	106,385
Interest expense	(9,665)		(12,122)		(29,241)	(36,180)
Income from continuing operations before income taxes	48,821		22,437		121,195	69,766
Income tax (expense) benefit	(13,833)		(8,270)		(24,043)	(25,757)
Income from continuing operations	34,988		14,167		97,152	44,009
Net income	34,651		13,796		96,939	43,664
Net Income (Loss) Attributable to Noncontrolling Interest	(1,804)		(498)		(5,795)	(2,438)
Amounts attributable to Harsco Corporation common stockholders:
Income from continuing operations, net of tax	33,184		13,669		91,357	41,571
Net income attributable to Harsco Corporation common stockholders	$ 32,847		$ 13,298		$ 91,144	$ 41,226
Basic earnings per common share attributable to Harsco Corporation common stockholders:
Continuing operations (in dollars per share)	$ 0.41		$ 0.17		$ 1.13	$ 0.52
Basic earnings per share attributable to Harsco Corporation common stockholders (in dollars per share)	0.41		0.16	[1]	1.13	0.51	[1]
Diluted earnings per common share attributable to Harsco Corporation common stockholders:
Continuing operations (in dollars per share)	0.40		0.16		1.09	0.50
Diluted earnings per share attributable to Harsco Corporation common stockholders (in dollars per share)	$ 0.39	[1]	$ 0.16		$ 1.09	$ 0.50
Service Revenues [Member]
Revenues from continuing operations:
Total revenues	$ 250,890		$ 246,144		$ 763,815	$ 738,059
Costs and expenses from continuing operations:
Cost of services and products sold	194,459		194,483		589,738	577,200
Product Revenues [Member]
Revenues from continuing operations:
Total revenues	194,585		138,509		521,670	414,033
Costs and expenses from continuing operations:
Cost of services and products sold	132,262		$ 95,849		367,218	$ 295,367
Difference between Revenue Guidance in Effect before and after Topic 606 | Accounting Standards Update 2014-09
Revenues from continuing operations:
Total revenues	(14,899)				(30,087)
Costs and expenses from continuing operations:
Selling, general and administrative costs	66				103
Total costs and expenses	(10,640)				(26,008)
Operating income from continuing operations	(4,259)				(4,079)
Interest expense	550				1,453
Income from continuing operations before income taxes	(3,709)				(2,626)
Income tax (expense) benefit	932				919
Income from continuing operations	(2,777)				(1,707)
Net income	(2,777)				(1,707)
Net Income (Loss) Attributable to Noncontrolling Interest	(10)				(8)
Amounts attributable to Harsco Corporation common stockholders:
Income from continuing operations, net of tax	(2,787)				(1,715)
Net income attributable to Harsco Corporation common stockholders	$ (2,787)				$ (1,715)
Basic earnings per common share attributable to Harsco Corporation common stockholders:
Continuing operations (in dollars per share)	$ (0.03)				$ (0.02)
Basic earnings per share attributable to Harsco Corporation common stockholders (in dollars per share)	(0.03)				(0.02)
Diluted earnings per common share attributable to Harsco Corporation common stockholders:
Continuing operations (in dollars per share)	(0.03)				(0.02)
Diluted earnings per share attributable to Harsco Corporation common stockholders (in dollars per share)	$ (0.03)				$ (0.02)
Difference between Revenue Guidance in Effect before and after Topic 606 | Accounting Standards Update 2014-09 | Service Revenues [Member]
Revenues from continuing operations:
Total revenues	$ 512				$ 4,182
Costs and expenses from continuing operations:
Cost of services and products sold	1,273				3,980
Difference between Revenue Guidance in Effect before and after Topic 606 | Accounting Standards Update 2014-09 | Product Revenues [Member]
Revenues from continuing operations:
Total revenues	(15,411)				(34,269)
Costs and expenses from continuing operations:
Cost of services and products sold	(11,979)				(30,091)
Calculated under Revenue Guidance in Effect before Topic 606 [Member]
Revenues from continuing operations:
Total revenues	430,576				1,255,398
Costs and expenses from continuing operations:
Selling, general and administrative costs	59,363				175,410
Total costs and expenses	377,726				1,112,202
Operating income from continuing operations	52,850				143,196
Interest expense	(9,115)				(27,788)
Income from continuing operations before income taxes	45,112				118,569
Income tax (expense) benefit	(12,901)				(23,124)
Income from continuing operations	32,211				95,445
Net income	31,874				95,232
Net Income (Loss) Attributable to Noncontrolling Interest	(1,814)				(5,803)
Amounts attributable to Harsco Corporation common stockholders:
Income from continuing operations, net of tax	30,397				89,642
Net income attributable to Harsco Corporation common stockholders	$ 30,060				$ 89,429
Basic earnings per common share attributable to Harsco Corporation common stockholders:
Continuing operations (in dollars per share)	$ 0.38				$ 1.11
Basic earnings per share attributable to Harsco Corporation common stockholders (in dollars per share)	0.37				1.11
Diluted earnings per common share attributable to Harsco Corporation common stockholders:
Continuing operations (in dollars per share)	0.36				1.07
Diluted earnings per share attributable to Harsco Corporation common stockholders (in dollars per share)	$ 0.36				$ 1.07
Calculated under Revenue Guidance in Effect before Topic 606 [Member] | Service Revenues [Member]
Revenues from continuing operations:
Total revenues	$ 251,402				$ 767,997
Costs and expenses from continuing operations:
Cost of services and products sold	195,732				593,718
Calculated under Revenue Guidance in Effect before Topic 606 [Member] | Product Revenues [Member]
Revenues from continuing operations:
Total revenues	179,174				487,401
Costs and expenses from continuing operations:
Cost of services and products sold	$ 120,283				$ 337,127
[1]	Does not total due to rounding

Recently Adopted and Recently_5

Recently Adopted and Recently Issued Accounting Standards - Condensed Consolidated Statements of Cash Flows (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Net income	$ 34,651	$ 13,796	$ 96,939	$ 43,664
Adjustments to reconcile net income to net cash used by operating activities:
Deferred income tax expense			1,996	2,018
Changes in assets and liabilities:
Accounts receivable			(29,022)	(26,633)
Inventories			(18,852)	(30,112)
Contract assets			(10,427)	0
Advances on contracts			(12,339)	(6,534)
Other assets and liabilities			(14,164)	8,200
Net Cash Provided by (Used in) Operating Activities			95,014	$ 82,905
Difference between Revenue Guidance in Effect before and after Topic 606 | Accounting Standards Update 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Net income	(2,777)		(1,707)
Adjustments to reconcile net income to net cash used by operating activities:
Deferred income tax expense			(919)
Changes in assets and liabilities:
Accounts receivable			8
Inventories			(34,923)
Contract assets			10,427
Advances on contracts			21,794
Other assets and liabilities			5,320
Net Cash Provided by (Used in) Operating Activities			0
Calculated under Revenue Guidance in Effect before Topic 606 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Net income	$ 31,874		95,232
Adjustments to reconcile net income to net cash used by operating activities:
Deferred income tax expense			1,077
Changes in assets and liabilities:
Accounts receivable			(29,014)
Inventories			(53,775)
Contract assets			0
Advances on contracts			9,455
Other assets and liabilities			(8,844)
Net Cash Provided by (Used in) Operating Activities			$ 95,014

Recently Adopted and Recently_6

Recently Adopted and Recently Issued Accounting Standards - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Mar. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Defined benefit pension income (expense)	$ (928)	$ 680	$ (2,671)	$ 2,054
Adoption of new accounting standard (See Note 2)					$ 2,375		$ 397
Stranded income tax effects in accumulated other comprehensive income						$ 21,000
Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Adoption of new accounting standard (See Note 2)	$ 100		$ 100		$ 3,895		$ (709)

Acquisitions - Narrative (Detai

Acquisitions - Narrative (Details) - Altek £ in Millions, $ in Millions	1 Months Ended		3 Months Ended
	May 31, 2018GBP (£)	May 31, 2018USD ($)	Sep. 30, 2018USD ($)	May 31, 2018USD ($)
Business Acquisition [Line Items]
Purchase price	£ 45	$ 60.1
Additional contingent consideration	£ 25			$ 33
Estimated preliminary fair value				16.3
Goodwill to be deductible for tax purposes (less than)				$ 1
Selling, General and Administrative Expenses
Business Acquisition [Line Items]
Costs associated with acquisition			$ 1

Acquisitions - Assets Acquired

Acquisitions - Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	3 Months Ended
	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017
Business Acquisition [Line Items]
Goodwill	$ 420,351		$ 401,758
Altek
Business Acquisition [Line Items]
Cash and cash equivalents	1,700	$ 1,700
Net working capital	(1,300)	(1,500)
Property, plant and equipment	3,300	3,300
Intangible assets	52,700	52,500
Goodwill	26,700	20,900
Net deferred tax liabilities	(8,500)	(8,500)
Other liabilities	(300)	(300)
Total identifiable net assets of Altek	74,300	$ 68,100
Measurement Period Adjustments
Net working capital	200
Intangible assets	200
Goodwill	5,800
Total identifiable net assets of Altek	$ 6,200

Acquisitions - Intangible Asset

Acquisitions - Intangible Assets and Amortization Periods (Details) - Altek - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2018	Jun. 30, 2018
Business Acquisition [Line Items]
Total identifiable intangible assets of Altek	$ 52.7	$ 52.7	$ 52.5
Measurement Period Adjustments	0.2
Customer related
Business Acquisition [Line Items]
Amortization Period		14 years 2 months 12 days
Total identifiable intangible assets of Altek	11.6	$ 11.6	11.5
Measurement Period Adjustments	0.1
Technology related
Business Acquisition [Line Items]
Amortization Period		10 years 3 months 18 days
Total identifiable intangible assets of Altek	36.6	$ 36.6	36.5
Measurement Period Adjustments	0.1
Trade names
Business Acquisition [Line Items]
Amortization Period		15 years
Total identifiable intangible assets of Altek	4.5	$ 4.5	$ 4.5
Measurement Period Adjustments	$ 0

Acquisitions - Changes in Fair

Acquisitions - Changes in Fair Value of Contingent Consideration (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Contingent Consideration
Balance, June 30, 2018	$ 10,097
Measurement period adjustment	6,177
Fair value adjustment	412	$ 0	$ 412	$ 0
Foreign currency translation	(298)
Balance, September 30, 2018	$ 16,388		$ 16,388

Accounts Receivable and Inven_3

Accounts Receivable and Inventories (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2016	Jan. 01, 2018	Dec. 31, 2017
Accounts receivable
Trade accounts receivable	$ 308,278		$ 308,278				$ 292,765
Less: Allowance for doubtful accounts	(4,113)		(4,113)				(4,731)
Trade accounts receivable, net	304,165		304,165			$ 288,566	288,034
Other receivables	55,156		55,156				20,224
Provision for doubtful accounts related to trade accounts receivable	(26)	$ 4,087	(182)	$ 5,262
Inventories
Finished goods	19,957		19,957				26,415
Work-in-process	22,175		22,175				24,367
Contracts-in-process	0		0				45,599
Raw materials and purchased parts	72,935		72,935				58,943
Stores and supplies	22,701		22,701				22,969
Inventories	137,768		137,768			$ 118,500	178,293
Inventory for Contracts
Contract costs accumulated to date							73,740
Estimated loss provisions for contracts-in-process							(28,141)
Contracts-in-process	0		0				45,599
Loss provision that exceeds accumulated contract costs	9,700		9,700				3,000
Net customer advances	54,004		54,004				117,958
Contract estimated forward loss provision for Harsco Rail Segment			1,800		$ 45,100
SBB [Member]
Inventory for Contracts
Net customer advances							$ 97,900
Revenues	$ 5,000	$ 0	$ 20,400
Contract 1 [Member] | SBB [Member]
Inventory for Contracts
Percentage complete	98.00%		98.00%
Contract 2 [Member] | SBB [Member]
Inventory for Contracts
Percentage complete	24.00%		24.00%

Property, Plant and Equipment_2

Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Property, Plant and Equipment
Gross property, plant and equipment	$ 1,803,926	$ 1,848,518
Less: Accumulated depreciation	(1,343,428)	(1,368,771)
Property, plant and equipment, net	460,498	479,747
Land
Property, Plant and Equipment
Gross property, plant and equipment	10,874	10,840
Land improvements
Property, Plant and Equipment
Gross property, plant and equipment	15,874	14,996
Buildings and improvements
Property, Plant and Equipment
Gross property, plant and equipment	192,011	198,582
Machinery and equipment
Property, Plant and Equipment
Gross property, plant and equipment	1,554,559	1,599,713
Construction in progress
Property, Plant and Equipment
Gross property, plant and equipment	$ 30,608	$ 24,387

Goodwill and Other Intangible_3

Goodwill and Other Intangible Assets - Changes in Carrying Amounts of Goodwill by Segment (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2018USD ($)
Changes in carrying amounts of goodwill
Balance at December 31, 2017	$ 401,758
Changes to goodwill	26,737
Foreign currency translation	(8,144)
Balance at September 30, 2018	420,351
Harsco Metals & Minerals Segment
Changes in carrying amounts of goodwill
Balance at December 31, 2017	381,893
Changes to goodwill	26,737
Foreign currency translation	(8,144)
Balance at September 30, 2018	400,486
Harsco Industrial Segment
Changes in carrying amounts of goodwill
Balance at December 31, 2017	6,839
Changes to goodwill	0
Foreign currency translation	0
Balance at September 30, 2018	6,839
Harsco Rail Segment
Changes in carrying amounts of goodwill
Balance at December 31, 2017	13,026
Changes to goodwill	0
Foreign currency translation	0
Balance at September 30, 2018	$ 13,026

Goodwill and Other Intangible_4

Goodwill and Other Intangible Assets - Other Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Intangible Assets, by category
Gross Carrying Amount	$ 191,921		$ 191,921		$ 202,162
Accumulated Amortization	108,323		108,323		163,911
Amortization expense for intangible assets	2,395	$ 1,269	5,326	$ 3,868
Estimated amortization expense for next 5 years
2,018	7,900		7,900
2,019	9,750		9,750
2,020	9,250		9,250
2,021	8,800		8,800
2,022	8,500		8,500
Customer related
Intangible Assets, by category
Gross Carrying Amount	137,498		137,498		153,014
Accumulated Amortization	98,834		98,834		121,385
Patents
Intangible Assets, by category
Gross Carrying Amount	2,590		2,590		5,825
Accumulated Amortization	2,495		2,495		5,700
Technology related
Intangible Assets, by category
Gross Carrying Amount	36,666		36,666		26,131
Accumulated Amortization	1,851		1,851		26,131
Trade names
Intangible Assets, by category
Gross Carrying Amount	9,311		9,311		8,317
Accumulated Amortization	1,754		1,754		4,845
Other
Intangible Assets, by category
Gross Carrying Amount	5,856		5,856		8,875
Accumulated Amortization	$ 3,389		$ 3,389		$ 5,850

Debt and Credit Agreements (Det

Debt and Credit Agreements (Details) - USD ($)	3 Months Ended			9 Months Ended
	Sep. 30, 2018	Jun. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Debt Instrument [Line Items]
Loss on early extinguishment of debt	$ 125,000	$ 1,000,000	$ 0	$ 1,159,000	$ 0
Line of Credit [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 500,000,000			$ 500,000,000
Line of Credit [Member] | LIBOR
Debt Instrument [Line Items]
Variable rate basis spread				2.25%

Employee Benefit Plans (Details

Employee Benefit Plans (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Defined benefit plans:
Multiemployer pension plans	$ 492	$ 498	$ 1,512	$ 1,481
Defined contribution pension plans	2,306	3,278	7,888	8,306
Pension Plan | U.S. Plans
Defined benefit plans:
Service cost	10	10	31	32
Interest cost	2,391	2,469	7,172	7,408
Expected return on plan assets	(3,017)	(2,620)	(9,051)	(7,863)
Recognized prior service costs	0	8	0	24
Recognized loss	1,302	1,425	3,906	4,276
Settlement/curtailment losses			166	0
Defined benefit pension plans net periodic pension cost (benefit)	686	1,292	2,224	3,877
Defined benefit pension plan	5,958	4,112	9,309	5,054
Anticipated contributions to defined benefit pension plans during the remainder of the fiscal year	500		500
Pension Plan | International Plans
Defined benefit plans:
Service cost	401	426	1,195	1,243
Interest cost	5,498	5,843	16,612	17,349
Expected return on plan assets	(10,820)	(10,632)	(32,661)	(31,571)
Recognized prior service costs	(37)	48	(113)	139
Recognized loss	3,737	4,130	11,267	12,260
Settlement/curtailment losses			0	0
Defined benefit pension plans net periodic pension cost (benefit)	(1,221)	(185)	(3,700)	(580)
Defined benefit pension plan	3,219	$ 3,038	16,192	$ 14,338
Anticipated contributions to defined benefit pension plans during the remainder of the fiscal year	$ 2,400		$ 2,400

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income tax expense	$ 13,833	$ 8,270	$ 24,043	$ 25,757
Valuation allowance adjustment related to the acquisition of Altek			8,300
Unrecognized income tax benefits including interest and penalties	4,600		4,600
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	$ 900		$ 900
Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Change In Tax Rate, Deferred Tax Asset, Provisional Income Tax Expense					$ 48,700

Commitments and Contingencies (

Commitments and Contingencies (Details) $ in Millions	1 Months Ended	3 Months Ended	9 Months Ended
	Aug. 31, 2005USD ($)	Sep. 30, 2018USD ($)claimcase	Sep. 30, 2018USD ($)claimdefendantcase	Dec. 31, 2017USD ($)	Apr. 08, 2016USD ($)
Commitments and Contingencies
Minority interest		35.00%	35.00%
Reserve for loss contingencies		$ 7	$ 7
Lima Refinery Litigation
Commitments and Contingencies
Loss contingency damages sought					$ 317
Brazilian Tax Disputes - Jan 2004 through May 2005 | Sao Paulo State Revenue Authority
Commitments and Contingencies
Damages sought - principal			2
Damages sought - interest, penalties and fees		2	20
Amount of damages sought		9
Brazilian Tax Disputes - Jan 2002 through Dec 2003 | Sao Paulo State Revenue Authority
Commitments and Contingencies
Damages sought - principal	$ 1.5
Damages sought - interest, penalties and fees	4.8
Amount of damages sought	$ 6.3
Brazilian Labor Claims
Commitments and Contingencies
Loss contingency reserves		$ 7.4	$ 7.4	$ 9.6
Other
Commitments and Contingencies
Approximate number of defendants that includes the company named in legal actions | defendant			90
Number of pending claims | claim		17,287	17,287
Number of claims dismissed to date by stipulation or summary judgment prior to trial | case			28,007
Other | Active or In Extremis docket
Commitments and Contingencies
Number of pending claims | claim		33	33
Other | Minimum
Commitments and Contingencies
Amount of damages sought			$ 20
Other | Maximum
Commitments and Contingencies
Amount of damages sought			$ 25
Other | New York County as managed by the New York Supreme Court
Commitments and Contingencies
Number of pending claims | case		16,737	16,737
Other | New York County as managed by the New York Supreme Court | Pending And Future Litigation, Deferred Or Inactive Docket
Commitments and Contingencies
Number of pending claims | claim		16,704	16,704
Other | New York State Supreme Court, Counties Excluding New York County
Commitments and Contingencies
Number of pending claims | case		113	113
Other | Courts Located In States Other Than New York
Commitments and Contingencies
Number of pending claims | case		437	437
Consolidated Revenues | Subsidiary Concentration Risk
Commitments and Contingencies
Concentration risk, percentage			2.00%

Reconciliation of Basic and D_3

Reconciliation of Basic and Diluted Shares - Reconciliation of Basic and Diluted Shares (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Earnings Per Share [Abstract]
Income from continuing operations, net of tax	$ 33,184	$ 13,669	$ 91,357	$ 41,571
Weighted-average shares outstanding - basic (in shares)	80,950	80,637	80,821	80,519
Dilutive effect of stock-based compensation (in shares)	2,929	2,499	2,869	2,234
Weighted-average shares outstanding - diluted (in shares)	83,879	83,136	83,690	82,753
Earnings (loss) from continuing operations per common share, attributable to Harsco Corporation common stockholders:
Basic (in dollars per share)	$ 0.41	$ 0.17	$ 1.13	$ 0.52
Diluted (in dollars per share)	$ 0.40	$ 0.16	$ 1.09	$ 0.50

Reconciliation of Basic and D_4

Reconciliation of Basic and Diluted Shares - Antidilutive Securities Excluded from Computation of Earnings per Share (Details) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Stock options
Antidilutive securities
Number of securities not included in computation of diluted earnings per share (in shares)	0	55	0	55
Stock appreciation rights
Antidilutive securities
Number of securities not included in computation of diluted earnings per share (in shares)	75	526	349	918
Performance share units
Antidilutive securities
Number of securities not included in computation of diluted earnings per share (in shares)	0	0	0	212

Derivative Instruments, Hedgi_3

Derivative Instruments, Hedging Activities and Fair Value - Fair Value of Outstanding Derivative Contracts (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Derivative contracts
Asset derivatives	$ 15,304	$ 5,878
Liability derivatives	1,723	8,491
Foreign currency exchange forward contracts | Other current assets
Derivative contracts
Asset derivatives	9,951	5,244
Foreign currency exchange forward contracts | Other current liabilities
Derivative contracts
Liability derivatives	1,692	7,123
Interest rate swaps | Other current assets
Derivative contracts
Asset derivatives	1,900	464
Interest rate swaps | Other assets
Derivative contracts
Asset derivatives	3,453	170
Interest rate swaps | Other liabilities
Derivative contracts
Liability derivatives	31	1,368
Fair Value of Derivatives Designated as Hedging Instruments
Derivative contracts
Asset derivatives	7,562	2,963
Liability derivatives	140	1,521
Fair Value of Derivatives Designated as Hedging Instruments | Foreign currency exchange forward contracts | Other current assets
Derivative contracts
Asset derivatives	2,209	2,329
Fair Value of Derivatives Designated as Hedging Instruments | Foreign currency exchange forward contracts | Other current liabilities
Derivative contracts
Liability derivatives	109	153
Fair Value of Derivatives Designated as Hedging Instruments | Interest rate swaps | Other current assets
Derivative contracts
Asset derivatives	1,900	464
Fair Value of Derivatives Designated as Hedging Instruments | Interest rate swaps | Other assets
Derivative contracts
Asset derivatives	3,453	170
Fair Value of Derivatives Designated as Hedging Instruments | Interest rate swaps | Other liabilities
Derivative contracts
Liability derivatives	31	1,368
Fair Value of Derivatives Not Designated as Hedging Instruments
Derivative contracts
Asset derivatives	7,742	2,915
Liability derivatives	1,583	6,970
Fair Value of Derivatives Not Designated as Hedging Instruments | Foreign currency exchange forward contracts | Other current assets
Derivative contracts
Asset derivatives	7,742	2,915
Fair Value of Derivatives Not Designated as Hedging Instruments | Foreign currency exchange forward contracts | Other current liabilities
Derivative contracts
Liability derivatives	1,583	6,970
Fair Value of Derivatives Not Designated as Hedging Instruments | Interest rate swaps | Other current assets
Derivative contracts
Asset derivatives	0	0
Fair Value of Derivatives Not Designated as Hedging Instruments | Interest rate swaps | Other assets
Derivative contracts
Asset derivatives	0	0
Fair Value of Derivatives Not Designated as Hedging Instruments | Interest rate swaps | Other liabilities
Derivative contracts
Liability derivatives	$ 0	$ 0

Derivative Instruments, Hedgi_4

Derivative Instruments, Hedging Activities and Fair Value - Narrative (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2022	Dec. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
Foreign Currency Derivatives
Liabilities	$ 1,356,026,000		$ 1,356,026,000				$ 1,325,152,000	$ 1,363,520,000
Pre-tax net gains (losses) on certain loans designated as hedges of net investments in foreign subsidiaries	(800,000)	$ 7,600,000	(7,500,000)	$ 17,100,000
Fair value of long-term debt	649,000,000		649,000,000					599,100,000
Carrying value of long-term debt	646,500,000		646,500,000					593,700,000
Subject to Master Netting Agreements
Foreign Currency Derivatives
Net assets	1,300,000		1,300,000
Liabilities								200,000
Foreign currency exchange forward contracts
Foreign Currency Derivatives
U.S. Dollar Equivalent	652,600,000		652,600,000					$ 671,900,000
Term Loan Facility, Fixed-Rate | Term Loan
Foreign Currency Derivatives
Principal amount	$ 300,000,000		$ 300,000,000
LIBOR | Scenario, Forecast | Term Loan Facility, Fixed-Rate | Term Loan
Foreign Currency Derivatives
Variable rate basis spread					3.12%	1.65%

Derivative Instruments, Hedgi_5

Derivative Instruments, Hedging Activities and Fair Value - Effect of Derivative Instruments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Jan. 01, 2018	Dec. 31, 2017
Effect of derivative instruments
Amount of Gain (Loss) Recognized in Other Comprehensive Income ("OCI") on Derivative - Effective Portion	$ 866	$ 1,926	$ 8,026	$ 23
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income - Effective Portion	(58)	252	(1,274)	560
Amount of Gain (Loss) Recognized in Income on Derivative - Ineffective Portion and Amount Excluded from Effectiveness Testing	0	(103)		(420)
Accumulated other comprehensive loss	(555,291)		(555,291)		$ (548,102)	$ (546,582)
Foreign currency exchange forward contracts
Effect of derivative instruments
Amount of Gain (Loss) Recognized in Other Comprehensive Income ("OCI") on Derivative - Effective Portion	(410)	2,333	1,369	3,096
Amount of Gain (Loss) Recognized in Income on Derivative - Ineffective Portion and Amount Excluded from Effectiveness Testing	0	0
Foreign currency exchange forward contracts | Cost of services and products sold
Effect of derivative instruments
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income - Effective Portion	(3)	0	(112)	(185)
Derivatives Not Designated as Hedging Instruments
Amount of Gain (Loss) Recognized in Income on Derivative	3,194	(7,025)	13,459	(18,764)
Interest rate swaps
Effect of derivative instruments
Amount of Gain (Loss) Recognized in Other Comprehensive Income ("OCI") on Derivative - Effective Portion	1,276	(335)	6,657	(2,878)
Interest rate swaps | Interest Expense [Member]
Effect of derivative instruments
Amount of Gain (Loss) Recognized in Other Comprehensive Income ("OCI") on Derivative - Effective Portion	(367)		(602)
Cross currency interest rate swaps
Effect of derivative instruments
Amount of Gain (Loss) Recognized in Other Comprehensive Income ("OCI") on Derivative - Effective Portion	0	(72)	0	(195)
Cross currency interest rate swaps | Cost of services and products sold
Effect of derivative instruments
Amount of Gain (Loss) Recognized in Income on Derivative - Ineffective Portion and Amount Excluded from Effectiveness Testing	0	(103)	0	(420)
Cross currency interest rate swaps | Interest Expense [Member]
Effect of derivative instruments
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income - Effective Portion	312	$ 252	960	$ 745
Accounting Standards Update 2014-09 | Difference between Revenue Guidance in Effect before and after Topic 606
Effect of derivative instruments
Accumulated other comprehensive loss	$ 1,679		$ 1,679		$ (1,520)

Review of Operations by Segme_3

Review of Operations by Segment (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2018	Jun. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Operations by segment
Total revenues	$ 445,475		$ 384,653	$ 1,285,485	$ 1,152,092
Operating income from continuing operations	57,109		34,629	147,275	106,385
Interest income	574		610	1,649	1,615
Interest expense	(9,665)		(12,122)	(29,241)	(36,180)
Defined benefit pension income (expense)	(928)		680	(2,671)	2,054
Loss on early extinguishment of debt	(125)	$ (1,000)	0	(1,159)	0
Income from continuing operations before income taxes	48,821		22,437	121,195	69,766
Depreciation and Amortization	33,373		33,005	99,944	97,508
Capital Expenditures	34,806		23,431	91,302	64,131
Operating Segments
Operations by segment
Operating income from continuing operations	62,297		40,958	162,854	124,722
Corporate
Operations by segment
Total revenues	0		38	74	107
Operating income from continuing operations	(5,188)		(6,329)	(15,579)	(18,337)
Depreciation and Amortization	1,332		1,449	4,346	4,399
Capital Expenditures	297		297	673	1,075
Harsco Metals & Minerals Segment | Operating Segments
Operations by segment
Total revenues	268,881		255,163	805,924	761,503
Operating income from continuing operations	29,338		23,613	92,734	80,834
Depreciation and Amortization	29,007		28,636	86,724	84,444
Capital Expenditures	29,870		20,994	79,469	58,065
Harsco Industrial Segment | Operating Segments
Operations by segment
Total revenues	93,912		78,318	269,575	217,766
Operating income from continuing operations	13,959		12,954	40,550	25,088
Depreciation and Amortization	1,971		1,826	5,708	5,509
Capital Expenditures	1,891		1,678	5,894	3,226
Harsco Rail Segment | Operating Segments
Operations by segment
Total revenues	82,682		51,134	209,912	172,716
Operating income from continuing operations	19,000		4,391	29,570	18,800
Depreciation and Amortization	1,063		1,094	3,166	3,156
Capital Expenditures	$ 2,748		$ 462	$ 5,266	$ 1,765

Revenue Recognition - Narrative

Revenue Recognition - Narrative (Details) $ in Millions	9 Months Ended
	Sep. 30, 2018USD ($)
Harsco Metals & Minerals Segment | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2018-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 44.6
Period of expected timing of satisfaction	1 year
Harsco Metals & Minerals Segment | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 40.1
Period of expected timing of satisfaction	1 year
Harsco Metals & Minerals Segment | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 25.6
Period of expected timing of satisfaction	1 year
Harsco Metals & Minerals Segment | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 22.5
Period of expected timing of satisfaction	1 year
Harsco Metals & Minerals Segment | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Period of expected timing of satisfaction	1 year
Harsco Metals & Minerals Segment | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: (nil)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 147.5
Harsco Rail Segment | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2018-07-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	46.6
Harsco Rail Segment | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-07-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 63
Period of expected timing of satisfaction	1 year
Harsco Rail Segment | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-07-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 54.5
Period of expected timing of satisfaction	1 year
Harsco Rail Segment | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-07-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 28
Period of expected timing of satisfaction	1 year
Harsco Rail Segment | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Period of expected timing of satisfaction	1 year
Harsco Rail Segment | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Period of expected timing of satisfaction	1 year
Harsco Rail Segment | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: (nil)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 200.3

Revenue Recognition - Revenues

Revenue Recognition - Revenues by Primary Geographical Markets (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Disaggregation of Revenue [Line Items]
Total revenues	$ 445,475	$ 384,653	$ 1,285,485	$ 1,152,092
On-site services and material logistics, product quality improvement and resource recovery for iron, steel and metals manufacturing; as well as value- added environmental solutions for industrial co-products
Disaggregation of Revenue [Line Items]
Total revenues	268,881	255,163	805,924	761,503
Railway track maintenance services and equipment
Disaggregation of Revenue [Line Items]
Total revenues	82,682	51,134	209,912	172,716
Air-cooled heat exchangers
Disaggregation of Revenue [Line Items]
Total revenues	52,093	38,248	144,936	102,483
Industrial grating and fencing products
Disaggregation of Revenue [Line Items]
Total revenues	31,782	29,659	94,325	86,952
Heat transfer products
Disaggregation of Revenue [Line Items]
Total revenues	10,037	10,411	30,314	28,331
General Corporate
Disaggregation of Revenue [Line Items]
Total revenues		38	74	107
North America
Disaggregation of Revenue [Line Items]
Total revenues	230,191	178,735	635,176	536,210
Western Europe
Disaggregation of Revenue [Line Items]
Total revenues	108,131	99,976	330,223	305,583
Latin America
Disaggregation of Revenue [Line Items]
Total revenues	42,683	47,419	133,324	138,341
Asia-Pacific
Disaggregation of Revenue [Line Items]
Total revenues	44,855	40,812	128,217	120,229
Middle East and Africa
Disaggregation of Revenue [Line Items]
Total revenues	12,370	10,849	36,073	31,358
Eastern Europe
Disaggregation of Revenue [Line Items]
Total revenues	7,245	6,862	22,472	20,371
Harsco Metals & Minerals Segment
Disaggregation of Revenue [Line Items]
Total revenues	268,881	255,163	805,924	761,503
Harsco Metals & Minerals Segment | On-site services and material logistics, product quality improvement and resource recovery for iron, steel and metals manufacturing; as well as value- added environmental solutions for industrial co-products
Disaggregation of Revenue [Line Items]
Total revenues	268,881	255,163	805,924	761,503
Harsco Metals & Minerals Segment | Railway track maintenance services and equipment
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Harsco Metals & Minerals Segment | Air-cooled heat exchangers
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Harsco Metals & Minerals Segment | Industrial grating and fencing products
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Harsco Metals & Minerals Segment | Heat transfer products
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Harsco Metals & Minerals Segment | General Corporate
Disaggregation of Revenue [Line Items]
Total revenues		0	0	0
Harsco Metals & Minerals Segment | North America
Disaggregation of Revenue [Line Items]
Total revenues	78,844	70,325	229,771	208,317
Harsco Metals & Minerals Segment | Western Europe
Disaggregation of Revenue [Line Items]
Total revenues	97,411	89,481	291,742	278,717
Harsco Metals & Minerals Segment | Latin America
Disaggregation of Revenue [Line Items]
Total revenues	36,165	41,656	115,011	119,434
Harsco Metals & Minerals Segment | Asia-Pacific
Disaggregation of Revenue [Line Items]
Total revenues	36,846	35,990	110,855	103,306
Harsco Metals & Minerals Segment | Middle East and Africa
Disaggregation of Revenue [Line Items]
Total revenues	12,370	10,849	36,073	31,358
Harsco Metals & Minerals Segment | Eastern Europe
Disaggregation of Revenue [Line Items]
Total revenues	7,245	6,862	22,472	20,371
Harsco Industrial Segment
Disaggregation of Revenue [Line Items]
Total revenues	93,912	78,318	269,575	217,766
Harsco Industrial Segment | On-site services and material logistics, product quality improvement and resource recovery for iron, steel and metals manufacturing; as well as value- added environmental solutions for industrial co-products
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Harsco Industrial Segment | Railway track maintenance services and equipment
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Harsco Industrial Segment | Air-cooled heat exchangers
Disaggregation of Revenue [Line Items]
Total revenues	52,093	38,248	144,936	102,483
Harsco Industrial Segment | Industrial grating and fencing products
Disaggregation of Revenue [Line Items]
Total revenues	31,782	29,659	94,325	86,952
Harsco Industrial Segment | Heat transfer products
Disaggregation of Revenue [Line Items]
Total revenues	10,037	10,411	30,314	28,331
Harsco Industrial Segment | General Corporate
Disaggregation of Revenue [Line Items]
Total revenues		0	0	0
Harsco Industrial Segment | North America
Disaggregation of Revenue [Line Items]
Total revenues	88,524	72,260	254,556	197,776
Harsco Industrial Segment | Western Europe
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Harsco Industrial Segment | Latin America
Disaggregation of Revenue [Line Items]
Total revenues	5,388	5,026	15,019	16,916
Harsco Industrial Segment | Asia-Pacific
Disaggregation of Revenue [Line Items]
Total revenues	0	1,032	0	3,074
Harsco Industrial Segment | Middle East and Africa
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Harsco Industrial Segment | Eastern Europe
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Harsco Rail Segment
Disaggregation of Revenue [Line Items]
Total revenues	82,682	51,134	209,912	172,716
Harsco Rail Segment | On-site services and material logistics, product quality improvement and resource recovery for iron, steel and metals manufacturing; as well as value- added environmental solutions for industrial co-products
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Harsco Rail Segment | Railway track maintenance services and equipment
Disaggregation of Revenue [Line Items]
Total revenues	82,682	51,134	209,912	172,716
Harsco Rail Segment | Air-cooled heat exchangers
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Harsco Rail Segment | Industrial grating and fencing products
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Harsco Rail Segment | Heat transfer products
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Harsco Rail Segment | General Corporate
Disaggregation of Revenue [Line Items]
Total revenues		0	0	0
Harsco Rail Segment | North America
Disaggregation of Revenue [Line Items]
Total revenues	62,823	36,112	150,775	130,010
Harsco Rail Segment | Western Europe
Disaggregation of Revenue [Line Items]
Total revenues	10,720	10,495	38,481	26,866
Harsco Rail Segment | Latin America
Disaggregation of Revenue [Line Items]
Total revenues	1,130	737	3,294	1,991
Harsco Rail Segment | Asia-Pacific
Disaggregation of Revenue [Line Items]
Total revenues	8,009	3,790	17,362	13,849
Harsco Rail Segment | Middle East and Africa
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Harsco Rail Segment | Eastern Europe
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Corporate
Disaggregation of Revenue [Line Items]
Total revenues	0	38	74	107
Corporate | On-site services and material logistics, product quality improvement and resource recovery for iron, steel and metals manufacturing; as well as value- added environmental solutions for industrial co-products
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Corporate | Railway track maintenance services and equipment
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Corporate | Air-cooled heat exchangers
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Corporate | Industrial grating and fencing products
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Corporate | Heat transfer products
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Corporate | General Corporate
Disaggregation of Revenue [Line Items]
Total revenues		38	74	107
Corporate | North America
Disaggregation of Revenue [Line Items]
Total revenues	0	38	74	107
Corporate | Western Europe
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Corporate | Latin America
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Corporate | Asia-Pacific
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Corporate | Middle East and Africa
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Corporate | Eastern Europe
Disaggregation of Revenue [Line Items]
Total revenues	$ 0	$ 0	$ 0	$ 0

Revenue Recognition - Contract

Revenue Recognition - Contract Assets and Advances on Contracts (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Jan. 01, 2018	Dec. 31, 2017
Contract assets:
Current portion of contract assets	$ 27,870	$ 18,248	$ 0
Contract assets	3,566	3,566	0
Total contract assets	31,436		0
Advances on contracts:
Current portion of advances on contracts	43,682	39,451	117,958
Advances on contracts	10,322	$ 24,564	0
Total advances on contracts	$ 54,004		$ 117,958

Other (Income) Expenses, Net (D

Other (Income) Expenses, Net (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Other Income and Expenses [Abstract]
Employee termination benefit costs	$ 1,037	$ 2,536	$ 3,249	$ 4,947
Net gains	(1,262)	(4,821)	(2,359)	(4,815)
Other costs to exit activities	11	327	475	495
Impaired asset write-downs	0	539	113	820
Contingent consideration adjustments	412	0	412	0
Other	430	182	(320)	282
Other (income) expenses, net	$ 628	$ (1,237)	$ 1,570	$ 1,729

Components of Accumulated Oth_3

Components of Accumulated Other Comprehensive Loss - Accumulated Other Comprehensive Income Loss (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Mar. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Components of Accumulated Other Comprehensive Income [Roll Forward]
Balances			$ 215,165	$ 137,563
Accumulated other comprehensive loss					$ (2,375)		$ (397)
Other comprehensive income (loss) before reclassifications			(24,151)	11,935
Amounts reclassified from accumulated other comprehensive loss			14,350	15,471
Total other comprehensive income	$ 1,225	$ 10,885	(9,801)	27,406
Other comprehensive loss attributable to noncontrolling interests			2,612	(2,235)
Other comprehensive income (loss) attributable to Harsco Corporation			(7,189)	25,171
Balances	304,391	210,018	304,391	210,018
Cumulative Foreign Exchange Translation Adjustments
Components of Accumulated Other Comprehensive Income [Roll Forward]
Balances			(111,567)	(144,534)
Other comprehensive income (loss) before reclassifications			(40,157)	42,391
Amounts reclassified from accumulated other comprehensive loss			0	0
Total other comprehensive income			(40,157)	42,391
Other comprehensive loss attributable to noncontrolling interests			2,612	(2,235)
Other comprehensive income (loss) attributable to Harsco Corporation			(37,545)	40,156
Balances	(149,112)	(104,378)	(149,112)	(104,378)
Effective Portion of Deriviatives Designated as Hedging Instruments
Components of Accumulated Other Comprehensive Income [Roll Forward]
Balances			808	(1,089)
Other comprehensive income (loss) before reclassifications			6,055	1,133
Amounts reclassified from accumulated other comprehensive loss			26	338
Total other comprehensive income			6,081	1,471
Other comprehensive loss attributable to noncontrolling interests			0	0
Other comprehensive income (loss) attributable to Harsco Corporation			6,081	1,471
Balances	5,369	382	5,369	382
Cumulative Unrecognized Actuarial Losses on Pension Obligations
Components of Accumulated Other Comprehensive Income [Roll Forward]
Balances			(435,840)	(461,094)
Other comprehensive income (loss) before reclassifications			9,970	(31,600)
Amounts reclassified from accumulated other comprehensive loss			14,324	15,133
Total other comprehensive income			24,294	(16,467)
Other comprehensive loss attributable to noncontrolling interests			0	0
Other comprehensive income (loss) attributable to Harsco Corporation			24,294	(16,467)
Balances	(411,546)	(477,561)	(411,546)	(477,561)
Unrealized Loss on Marketable Securities
Components of Accumulated Other Comprehensive Income [Roll Forward]
Balances			17	(5)
Other comprehensive income (loss) before reclassifications			(19)	11
Amounts reclassified from accumulated other comprehensive loss			0	0
Total other comprehensive income			(19)	11
Other comprehensive loss attributable to noncontrolling interests			0	0
Other comprehensive income (loss) attributable to Harsco Corporation			(19)	11
Balances	(2)	6	(2)	6
Accumulated Other Comprehensive Loss
Components of Accumulated Other Comprehensive Income [Roll Forward]
Balances			(546,582)	(606,722)
Accumulated other comprehensive loss					$ 1,520
Total other comprehensive income			(7,189)	25,171
Balances	$ (555,291)	$ (581,551)	(555,291)	$ (581,551)
Accounting Standards Update 2014-09 | Cumulative Foreign Exchange Translation Adjustments
Components of Accumulated Other Comprehensive Income [Roll Forward]
Balances			(111,567)
Accounting Standards Update 2014-09 | Effective Portion of Deriviatives Designated as Hedging Instruments
Components of Accumulated Other Comprehensive Income [Roll Forward]
Balances			(712)
Accumulated other comprehensive loss						$ (1,520)
Accounting Standards Update 2014-09 | Cumulative Unrecognized Actuarial Losses on Pension Obligations
Components of Accumulated Other Comprehensive Income [Roll Forward]
Balances			(435,840)
Accounting Standards Update 2014-09 | Unrealized Loss on Marketable Securities
Components of Accumulated Other Comprehensive Income [Roll Forward]
Balances			17
Accounting Standards Update 2014-09 | Accumulated Other Comprehensive Loss
Components of Accumulated Other Comprehensive Income [Roll Forward]
Balances			$ (548,102)
Accumulated other comprehensive loss						$ (1,520)

Components of Accumulated Oth_4

Components of Accumulated Other Comprehensive Loss - Reclassification out of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Interest expense	$ 9,665	$ 12,122	$ 29,241	$ 36,180
Income from continuing operations before income taxes	48,821	22,437	121,195	69,766
Income tax expense (benefit)	13,833	8,270	24,043	25,757
Net income	34,651	13,796	96,939	43,664
Amount Reclassified from Accumulated Other Comprehensive Loss | Cumulative Unrecognized Actuarial Losses on Pension Obligations
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Income from continuing operations before income taxes	5,002	5,614	15,226	16,699
Income tax expense (benefit)	(289)	(523)	(902)	(1,566)
Net income	4,713	5,091	14,324	15,133
Amount Reclassified from Accumulated Other Comprehensive Loss | Effective Portion of Deriviatives Designated as Hedging Instruments
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Income from continuing operations before income taxes	(58)	252	246	560
Income tax expense (benefit)	(13)	(99)	(220)	(222)
Net income	(71)	153	26	338
Amount Reclassified from Accumulated Other Comprehensive Loss | Effective Portion of Deriviatives Designated as Hedging Instruments | Foreign currency exchange forward contracts
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Product revenues	(3)	0	(112)	(189)
Cost of services and products sold	0	0	0	4
Amount Reclassified from Accumulated Other Comprehensive Loss | Effective Portion of Deriviatives Designated as Hedging Instruments | Cross currency interest rate swaps
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Interest expense	312	252	960	745
Amount Reclassified from Accumulated Other Comprehensive Loss | Effective Portion of Deriviatives Designated as Hedging Instruments | Interest rate swaps
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Interest expense	(367)	0	(602)	0
Amount Reclassified from Accumulated Other Comprehensive Loss | Actuarial losses
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Defined benefit pension income (expense)	5,039	5,558	15,173	16,536
Amount Reclassified from Accumulated Other Comprehensive Loss | Prior service costs (benefits)
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Defined benefit pension income (expense)	(37)	56	(113)	163
Amount Reclassified from Accumulated Other Comprehensive Loss | Settlement/curtailment losses
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Defined benefit pension income (expense)	$ 0	$ 0	$ 166	$ 0