Enviri (NVRI) 10-K 20 Feb 25 2024 FY Annual report Financial data

Cover

Cover - USD ($)	12 Months Ended
	Dec. 31, 2024	Feb. 13, 2025	Jun. 30, 2024
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Transition Report	false
Entity File Number	001-03970
Entity Registrant Name	ENVIRI CORPORATION
Entity Tax Identification Number	23-1483991
Entity Address, Address Line One	Two Logan Square100-120 North 18th Street, 17th Floor,
Entity Address, City or Town	Philadelphia,
Entity Address, State or Province	PA
Entity Address, Postal Zip Code	19103
City Area Code	267
Local Phone Number	857-8715
Title of 12(b) Security	Common stock, par value $1.25 per share
Trading Symbol	NVRI
Security Exchange Name	NYSE
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Document Financial Statement Error Correction	false
Entity Shell Company	false
Entity Public Float			$ 658,406,743
Entity Common Stock, Shares Outstanding		80,197,777
Current Fiscal Year End Date	--12-31
Entity Central Index Key	0000045876
Document Period End Date	Dec. 31, 2024
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	FY
Amendment Flag	false
Documents Incorporated by Reference	DOCUMENTS INCORPORATED BY REFERENCE Selected portions of the 2025 Proxy Statement are incorporated by reference into Part III of this Report.
Entity Incorporation, State or Country Code	DE

Audit Information

Audit Information	12 Months Ended
	Dec. 31, 2024
Auditor Information [Abstract]
Auditor Name	PricewaterhouseCoopers LLP
Auditor Location	Philadelphia, Pennsylvania
Auditor Firm ID	238

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Current assets:
Cash and cash equivalents	$ 88,359	$ 121,239
Restricted cash	1,799	3,375
Trade accounts receivable, net	260,690	338,187
Other receivables	40,439	40,565
Inventories	182,042	189,369
Current portion of contract assets	59,881	64,875
Prepaid Expense	62,435	58,723
Other current assets	14,880	11,023
Total current assets	710,525	827,356
Property, plant and equipment, net	664,292	707,397
Right-of-use assets, net	92,153	102,891
Goodwill	739,758	780,978
Intangible assets, net	298,438	327,983
Retirement plan assets	73,745	44,517
Deferred income tax assets	17,578	16,295
Other assets	53,744	47,281
Total assets	2,650,233	2,854,698
Current liabilities:
Short-term borrowings	8,144	14,871
Current maturities of long-term debt	21,004	15,558
Accounts payable	214,689	243,279
Accrued compensation	63,686	79,609
Income taxes payable	5,747	7,567
Provision for Loss on Contracts	54,320	52,919
Current portion of advances on contracts	13,265	38,313
Operating Lease, Liability, Current	26,049	28,775
Other current liabilities	159,478	174,342
Total current liabilities	566,382	655,233
Long-term debt	1,410,718	1,401,437
Retirement plan liabilities	27,019	45,087
Operating Lease, Liability, Noncurrent	67,998	75,476
Accrued Environmental Loss Contingencies, Noncurrent	46,585	25,682
Deferred tax liabilities	26,796	29,160
Other liabilities	55,136	47,215
Total liabilities	2,200,634	2,279,290
COMMITMENTS AND CONTINGENCIES
HARSCO CORPORATION STOCKHOLDERS' EQUITY
Common stock, par value $1.25 (issued 117,474,988 and 116,884,011 shares at December 31, 2024 and 2023, respectively)	146,844	146,105
Additional paid-in capital	255,102	238,416
Accumulated other comprehensive loss	(538,964)	(539,694)
Retained earnings	1,400,347	1,528,320
Treasury stock, at cost (37,277,211 and 37,049,176 shares at December 31, 2024 and 2023, respectively)	(851,881)	(849,996)
Total Harsco Corporation stockholders' equity	411,448	523,151
Noncontrolling interests	38,151	52,257
Total equity	449,599	575,408
Total liabilities and equity	$ 2,650,233	$ 2,854,698

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Statement of Financial Position [Abstract]
Common stock, par value (usd per share)	$ 1.25	$ 1.25
Common stock, shares issued	117,474,988	116,884,011	116,358,520	115,906,393
Treasury stock (in shares)	37,277,211	37,049,176	36,868,880	36,690,847
Retirement plan assets	$ 73,745	$ 44,517

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Revenues from continuing operations:
Total revenues	$ 2,342,645	$ 2,366,020	$ 2,133,981
Costs and expenses from continuing operations:
Cost of services and products sold			1,799,483
Selling, general and administrative costs	359,388	353,985	304,865
Research and development expenses	3,961	3,458	2,858
Goodwill and other intangible asset impairment charges	15,866	0	119,580
Property, plant and equipment impairment charge	23,444	14,099	0
Remeasurement of long-lived assets	10,695	0	0
Gain (Loss) on Disposition of Business	(10,478)	0	0
Other expenses	5,437	(1,591)	11,654
Total costs and expenses	2,310,900	2,286,082	2,234,877
Operating income (loss) from continuing operations	31,745	79,938	(100,896)
Interest income	6,795	6,809	3,829
Interest expense	(112,217)	(107,081)	(76,807)
Facility fees and debt-related income (expense)	(11,265)	(10,762)	(2,956)
Defined benefit pension income (expense)	(16,728)	(21,574)	8,933
Income (loss) from continuing operations before income taxes and equity income	(101,670)	(52,670)	(167,897)
Income tax expense	(17,066)	(30,866)	(4,856)
Equity income (loss) of unconsolidated entities, net	(10)	(761)	(178)
Income (loss) from continuing operations	(118,746)	(84,297)	(172,931)
Discontinued operations:
Income (loss) from discontinued businesses	(5,297)	(5,133)	(5,364)
Income tax benefit (expense) from discontinued businesses	1,382	1,332	1,864
Income (loss) from discontinued operations, net of tax	(3,915)	(3,801)	(3,500)
Net income (loss)	(122,661)	(88,098)	(176,431)
Less: Net income attributable to noncontrolling interests	(5,312)	1,977	(3,638)
Net income (loss) attributable to Enviri Corporation	(127,973)	(86,121)	(180,069)
Amounts attributable to Harsco Corporation common stockholders:
Income (loss) from continuing operations, net of tax	(124,058)	(82,320)	(176,569)
Income (loss) from discontinued operations, net of tax	(3,915)	(3,801)	(3,500)
Net income (loss) attributable to Enviri Corporation common stockholders	$ (127,973)	$ (86,121)	$ (180,069)
Weighted average shares of common stock outstanding	80,118	79,796	79,493
Basic earnings (loss) per share attributable to Enviri Corporation common stockholders:
Continuing operations (in dollars per share)	$ (1.55)	$ (1.03)	$ (2.22)
Discontinued operations (in dollars per share)	(0.05)	(0.05)	(0.04)
Basic earnings (loss) per share attributable to Harsco Corporation common stockholders (in dollars per share)	$ (1.60)	$ (1.08)	$ (2.27)
Diluted weighted average shares of stock outstanding	80,118	79,796	79,493
Diluted earnings (loss) per share attributable to Enviri Corporation common stockholders:
Continuing operations (in dollars per share)	$ (1.55)	$ (1.03)	$ (2.22)
Discontinued operations (in dollars per share)	(0.05)	(0.05)	(0.04)
Diluted earnings (loss) per share attributable to Harsco Corporation common stockholders (in dollars per share)	$ (1.60)	$ (1.08)	$ (2.27)
Services
Revenues from continuing operations:
Total revenues	$ 1,970,193	$ 1,931,712	$ 1,757,583
Costs and expenses from continuing operations:
Cost of services and products sold	1,557,473	1,511,689	1,438,421
Product
Revenues from continuing operations:
Total revenues	372,452	434,308	376,398
Costs and expenses from continuing operations:
Cost of services and products sold	$ 345,114	$ 404,442	$ 357,499

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (122,661)	$ (88,098)	$ (176,431)
Other comprehensive income (loss):
Foreign currency translation adjustments, net of deferred income taxes of $(836), $3,162 and $(6,752) in 2024, 2023 and 2022, respectively	(46,424)	28,988	(82,325)
Net gain (loss) on cash flow hedging instruments, net of deferred income taxes of $(1,398), $138 and $(1,284) in 2024, 2023 and 2022, respectively	4,239	(627)	3,181
Pension liability adjustments, net of deferred income taxes of $(5,937), $(2,693) and $(2,590) in 2024, 2023 and 2022, respectively	41,683	(1,041)	67,549
Unrealized gain (loss) on marketable securities, net of deferred income taxes of $(2), $(2) and $4 in 2024, 2023 and 2022, respectively	7	5	(12)
Other Comprehensive Income (Loss), Net of Tax, Total	(495)	27,325	(11,607)
Total comprehensive income (loss)	(123,156)	(60,773)	(188,038)
Less: Comprehensive (income) loss attributable to noncontrolling interests	(4,084)	2,594	472
Comprehensive income (loss) attributable to Enviri Corporation	$ (127,240)	$ (58,179)	$ (187,566)

CONSOLIDATED STATEMENTS OF CO_2

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Statement of Comprehensive Income [Abstract]
Foreign currency translation adjustments, deferred income taxes	$ (836)	$ 3,162	$ (6,752)
Net gains (losses) on cash flow hedging instruments, deferred income taxes	(1,398)	138	(1,284)
Pension liability adjustments, deferred income taxes	(5,937)	(2,693)	(2,590)
Unrealized gain (loss) on marketable securities, deferred income taxes	$ (2)	$ (2)	$ 4

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Cash flows from operating activities:
Net income (loss)	$ (122,661)	$ (88,098)	$ (176,431)
Adjustments to reconcile net income (loss) to net cash provided (used) by operating activities:
Depreciation	148,329	138,956	129,712
Amortization	31,471	32,408	34,137
(Gain) loss on early extinguishment of debt	0	0	(2,254)
Deferred income tax expense (benefit)	(12,798)	2,965	(13,561)
Equity (income) loss of unconsolidated entities, net	10	761	178
Dividends from unconsolidated entities	321	0	526
Goodwill and other intangible asset impairment charges	15,866	0	119,580
Remeasurement of long-lived assets	10,695	0	0
Gain (Loss) on Disposition of Business	(10,478)	0	0
Stock-based compensation	16,650	12,916	10,796
Other, net	(13,924)	(2,749)	(11,223)
Changes in assets and liabilities:
Accounts receivable	45,864	(38,487)	94,364
Income tax refunds receivable from acquisition, reimbursable to seller	0	0	7,687
Inventories	(7,534)	(3,410)	(16,798)
Contract assets	(11,412)	3,475	11,543
Increase (Decrease) In Right-Of_Use Assets	31,546	32,479	29,171
Property, plant and equipment impairment charge	23,444	14,099	0
Accounts payable	(15,038)	(5,090)	19,264
Accrued interest payable	(413)	221	(643)
Accrued compensation	(12,477)	33,871	(3,945)
Advances on contracts and other customer advances	(13,210)	(14,160)	(11,347)
Operating lease liabilities	(30,945)	(30,698)	(28,374)
Retirement plan liabilities, net	(6,140)	(3,968)	(34,136)
Other assets and liabilities	10,897	28,957	(7,719)
Net cash provided (used) by operating activities	78,063	114,448	150,527
Cash flows from investing activities:
Purchases of property, plant and equipment	(136,591)	(139,025)	(137,160)
Proceeds from sale of businesses	57,633	0	0
Proceeds from sales of assets	17,057	6,991	10,759
Expenditures for intangible assets	(1,309)	(503)	(184)
Proceeds from notes receivable	17,023	11,238	8,605
Payments for settlement of interest rate swaps	0	0	(2,304)
Net proceeds (payments) from settlement of foreign currency forward exchange contracts	12,114	4,251	20,950
Other investing activities, net	0	463	273
Net cash used by investing activities	(34,073)	(116,585)	(99,061)
Cash flows from financing activities:
Short-term borrowings, net	(6,198)	7,027	884
Current maturities and long-term debt:
Additions	240,544	201,997	224,445
Reductions	(274,153)	(164,475)	(256,310)
Dividends paid to noncontrolling interests	(17,095)	(5)	(4,841)
Sale of noncontrolling interests	0	0	1,901
Payments to Acquire Additional Interest in Subsidiaries	(1,197)	0	0
Contributions from noncontrolling interests	874	1,654	0
Stock-based compensation - Employee taxes paid	(1,885)	(1,426)	(1,949)
Payment of contingent consideration	0	0	(6,915)
Deferred financing costs	(4,290)	0	0
Net cash (used) provided by financing activities	(63,400)	44,772	(42,785)
Effect of exchange rate changes on cash, including restricted cash	(15,046)	(3,115)	(10,715)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect	(34,456)	39,520	(2,034)
Cash and cash equivalents, including restricted cash, at beginning of period	124,614	85,094	87,128
Cash and cash equivalents, including restricted cash, at end of period	90,158	124,614	85,094
Supplemental Cash Flow Information [Abstract]
Change in accrual for purchases of property, plant and equipment included in accounts payable	$ 1,660	$ (7,579)	$ 10,845

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY - USD ($) $ in Thousands	Total	Common Stock Issued	Treasury	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interests
Balances at Dec. 31, 2021	$ 805,770	$ 144,883	$ (846,622)	$ 215,528	$ 1,794,510	$ (560,139)	$ 57,610
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(176,431)				(180,069)		3,638
Cash dividends declared:
Noncontrolling interests	(4,841)						(4,841)
Total other comprehensive income (loss)	(11,607)					(7,497)	(4,110)
Proceeds from (Payments to) Noncontrolling Interests	1,901						1,901
Strategic venture exit	(598)						(598)
Stock appreciation rights exercised	(66)	29	(66)	(29)
Vesting of restricted stock units and other stock grants	(1,882)	536	(1,882)	(536)
Amortization of unearned stock-based compensation, net of forfeitures	10,796			10,796
Balances at Dec. 31, 2022	623,042	145,448	(848,570)	225,759	1,614,441	(567,636)	53,600
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(88,098)				(86,121)		(1,977)
Cash dividends declared:
Noncontrolling interests	(5)						(5)
Total other comprehensive income (loss)	27,325					27,942	(617)
Purchase of subsidiary shares from noncontrolling interest	0			398			(398)
Proceeds from (Payments to) Noncontrolling Interests	1,654						1,654
Vesting of restricted stock units and other stock grants	(1,426)	657	(1,426)	(657)
Amortization of unearned stock-based compensation, net of forfeitures	12,916			12,916
Balances at Dec. 31, 2023	575,408	146,105	(849,996)	238,416	1,528,320	(539,694)	52,257
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(122,661)				(127,973)		5,312
Cash dividends declared:
Noncontrolling interests	(17,095)						(17,095)
Total other comprehensive income (loss)	(495)					730	(1,225)
Purchase of subsidiary shares from noncontrolling interest	(1,197)			775			(1,972)
Proceeds from (Payments to) Noncontrolling Interests	874						874
Stock appreciation rights exercised	(2)	1	(2)	(1)
Vesting of restricted stock units and other stock grants	(1,883)	738	(1,883)	(738)
Amortization of unearned stock-based compensation, net of forfeitures	16,650			16,650
Balances at Dec. 31, 2024	$ 449,599	$ 146,844	$ (851,881)	$ 255,102	$ 1,400,347	$ (538,964)	$ 38,151

CONSOLIDATED STATEMENTS OF CH_2

CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Statement of Stockholders' Equity [Abstract]
Deferred income taxes	$ (8,173)	$ 605	$ (10,622)
Stock appreciation rights exercised (in shares)	603		16,671
Vesting of restricted stock units (in shares)	362,339	345,195	257,423

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2024
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Consolidation The Consolidated Financial Statements include all accounts of Enviri Corporation (the "Company"), all entities in which the Company has a controlling voting interest and variable interest entities required to be consolidated in accordance with U.S. GAAP. Intercompany accounts and transactions have been eliminated among consolidated entities. The Company's management has evaluated all activity of the Company and concluded that subsequent events are properly reflected in the Company's Consolidated Financial Statements and the accompanying notes as required by U.S. GAAP. Going Concern The Company's cash flow forecasts, combined with existing cash and cash equivalents and borrowings available under the Senior Secured Credit Facilities and the AR Facility, indicate sufficient liquidity to fund the Company's operations for at least the next twelve months. As such, the Company's Consolidated Financial Statements have been prepared on the basis that it will continue as a going concern for a period extending beyond twelve months from the date the consolidated financial statements are issued. This assessment includes the expected ability to meet required financial covenants and the continued ability to draw down on the Senior Secured Credit Facilities, as described in Note 8, Debt and Credit Agreements. Reclassifications During the year ended December 31, 2024, the Company determined that the held-for-sale criteria for Rail was no longer met and, as a result, the Company made reclassifications to prior year amounts previously classified as discontinued operations and assets held-for-sale in the Company's Consolidated Statements of Operations and Consolidated Balance Sheets, along with the accompanying notes to the Company's Consolidated Financial Statements. See Note 3, Discontinued Operations and Dispositions for further details. Other reclassifications have been made to prior year amounts to conform with current year classifications. These reclassifications did not have a material impact on the Company's Consolidated Financial Statements, including the notes thereto. Cash and Cash Equivalents Cash and cash equivalents include cash on hand, demand deposits and short-term investments that are highly liquid in nature and have an original maturity of three months or less. Restricted Cash The Company had restricted cash of $1.8 million and $3.4 million at December 31, 2024 and 2023, respectively, and the restrictions are primarily related to collateral provided for certain guarantees of the Company’s performance. Accounts Receivable Accounts receivable are stated at net realizable value, which represents the face value of the receivable, less an allowance for expected credit losses. The allowance for expected credit losses is maintained for expected lifetime losses resulting from the inability of customers to make required payments. The Company’s expected credit loss allowance methodology for accounts receivable is developed using historical collection experience, current and future economic and market conditions and a review of the current status of customers' trade accounts receivables. When required, the Company adjusts the loss-rate methodology to account for current conditions and reasonable and supportable expectations of future economic and market conditions. The Company generally assesses future economic conditions for a period which corresponds with the contractual life of its accounts receivable. Additionally, specific allowance amounts are established to record the appropriate provision for customers that have a higher probability of default. Accounts Receivable Securitization Facility Under the AR Facility, the Company and its subsidiaries continuously sell their trade receivables as they are originated to the Company’s SPE. The Company controls and, therefore, consolidates the SPE in its consolidated financial statements. The SPE transfers ownership and control of qualifying receivables to the banking counterparty to the AR Facility up to the maximum purchase commitment. The Company and its related subsidiaries have no continuing involvement in the transferred accounts receivable, other than collection and administrative responsibilities, and, once sold, the receivables are no longer available to satisfy creditors of the Company or the related subsidiaries. The Company accounts for receivables sold to the banking counterparty as a sale of financial assets and derecognizes the trade receivables from the Company's Consolidated Balance Sheets. Fees incurred for the AR Facility are deferred and are expensed over the term of the agreement. Unamortized costs are included in Other assets in the Company's Consolidated Balance Sheets and the related recognized expense is recorded in Facility fees and debt-related income (expense) on the Consolidated Statements of Operations. Inventories Inventories are accounted for using the average cost, first-in, first-out ("FIFO") or last-in, first-out ("LIFO") method. Inventory accounted for under the average cost and FIFO methods are stated at the lower of cost or net realizable value. Inventory accounted for under the LIFO method is stated at the lower of cost or market. See Note 5, Inventories Property, Plant and Equipment Property, plant and equipment ("PP&E") is recorded at cost and depreciated over the estimated useful lives of the assets using, principally, the straight-line method. When PP&E is retired from service, the cost of the retirement is charged to the allowance for depreciation to the extent of the accumulated depreciation and the balance is charged to income. Long-lived assets to be disposed of by sale are not depreciated while they are classified as held-for-sale. Leases The Company leases certain property and equipment under noncancelable lease agreements. The Company determines if a contract or arrangement contains a lease at inception. All leases are evaluated and classified as either an operating or finance lease. A lease is classified as a finance lease if any of the following criteria are met: (i) ownership of the underlying asset transfers to the Company by the end of the lease term; (ii) the lease contains an option to purchase the underlying asset that the Company is reasonably expected to exercise; (iii) the lease term is for a major part of the remaining economic life of the underlying asset; (iv) the present value of the sum of lease payments and any residual value guaranteed by the Company equals or exceeds substantially all of the fair value of the underlying asset; or (v) the underlying asset is of a specialized nature that it is expected to have no alternative use to the lessor at the end of the lease term. A lease that does not meet any of the finance lease classification criteria is classified as an operating lease. Operating leases are included as Right-of-use assets, net, Current portion of operating lease liabilities, and Operating lease liabilities on the Consolidated Balance Sheets. ROU assets and operating lease liabilities are recognized based on the present value of the future lease payments over the lease term at the commencement date. As most of the Company’s leases do not provide an implicit rate for use in determining the present value of future payments, the Company uses an incremental borrowing rate. This incremental borrowing rate reflects the creditworthiness of the Company for a lending period commensurate to the term of the lease, the standard lending practices related to such loans in the respective jurisdiction where the underlying assets are located and the local currency in which the lease is denominated. ROU assets also include any lease payments made prior to or at the lease commencement date and initial direct costs incurred, and may be reduced by any lease incentives received by the lessor. Lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Lease expense for minimum lease payments is recognized on a straight-line basis over the lease term, including rent abatement periods and rent holidays. Certain of the Company's leases are subject to annual changes in an index or are subject to adjustments for which the amounts are not readily determinable at lease inception. While lease liabilities are not remeasured as a result of changes to these costs, changes are treated as variable lease payments and recognized in the period in which the obligation for those payments were incurred. Finance leases are included as PP&E, net; Current maturities of long-term debt and Long-term debt on the Consolidated Balance Sheets. Finance lease costs are split between depreciation expense related to the asset and interest expense on the lease liability, using the effective rate charged by the lessor. The Company has lease agreements with both lease and non-lease components, which the Company has elected to account for as a single lease component. Additionally, the Company has elected not to record short-term leases, those with expected terms of twelve months or less, on the Company's Consolidated Balance Sheets. See Note 8, Debt and Credit Agreements Note 9, Leases Goodwill In accordance with U.S. GAAP, goodwill is not amortized and is tested for impairment at least annually or more frequently if indicators of impairment exist or if a decision is made to dispose of a business. Goodwill is assigned among and evaluated for impairment at the reporting unit level, which is defined as an operating segment or one level below an operating segment for which discrete financial information is available. A significant amount of judgment is involved in determining if an indicator of impairment has occurred. Such indicators may include declining cash flows or operating losses at the reporting unit level, a significant adverse change in legal factors or in the business climate, an adverse action or assessment by a regulator, unanticipated competition, a loss of key personnel or a more likely than not expectation that a reporting unit or a significant portion of a reporting unit will be sold or otherwise disposed of, among others. In applying the goodwill impairment test, the Company has the option to perform a qualitative test, a quantitative test or both. Under the qualitative test, the Company assesses qualitative factors to determine whether it is more likely than not that the fair value of the reporting units is less than its carrying value. Qualitative factors may include, but are not limited to, economic conditions, industry and market considerations, cost factors, overall financial performance of the reporting unit and other entity and reporting unit specific events. If after assessing these qualitative factors, the Company determines it is “more-likely-than-not” that the fair value of the reporting unit is less than the carrying value, the Company would perform a quantitative test. The quantitative approach of testing for goodwill impairment involves comparing the current fair value of each reporting unit to the carrying value, including goodwill. The Company uses a discounted cash flow model (“DCF model”) to estimate the current fair value of reporting units, as the Company's management believes forecasted operating cash flows are the best indicator of current fair value. A number of significant assumptions and estimates are involved in the preparation of DCF models including future revenues and operating margin growth, the weighted-average cost of capital (“WACC”), tax rates, capital spending, pension funding, the impact of business initiatives and working capital projections. These assumptions and estimates may vary significantly among reporting units. DCF models are based on approved long-range plans for the early years and historical relationships and projections for later years. WACC rates are derived from internal and external factors including, but not limited to, the average market price of the Company's stock, shares outstanding, book value of the Company's debt, the long-term risk-free interest rate, and both market and size-specific risk premiums. Due to the many variables noted above and the relative size of the Company's goodwill, differences in assumptions may have a material impact on the results of the Company's annual goodwill impairment testing. If the net book value of a reporting unit were to exceed the Company's determination of the current fair value, then an impairment charge would be recognized as the difference between the fair value and the carrying value. See Note 7, Goodwill and Other Intangible Assets Long-Lived Assets Impairments (Other than Goodwill) Long-lived assets or asset groups are reviewed for impairment when events and circumstances indicate that the carrying amount of an asset or asset group may not be recoverable. The Company's policy is to determine if an impairment loss exists when it is determined that the carrying amount of the asset or asset group exceeds the sum of the expected undiscounted future cash flows resulting from use of the asset or asset group and its eventual disposition. Impairment losses are measured as the amount by which the carrying amount of the asset or asset group exceeds its fair value, normally as determined in either open market transactions or through the use of a DCF model. Long-lived assets or asset groups to be disposed of are reported at the lower of the carrying amount or fair value less cost to sell. See Note 7, Goodwill and Other Intangible Assets and Note 18, Other (Income) Expenses, Net Deferred Financing Costs The Company has incurred debt issuance costs, which are recognized as a reduction of Long-term debt on the Consolidated Balance Sheets. Debt issuance costs are amortized and recognized over the contractual term of the related indebtedness or shorter period, if appropriate, based upon contractual terms in Interest expense on the Consolidated Statements of Operations. Whenever indebtedness is modified from its original terms, an evaluation is made whether an accounting modification or extinguishment has occurred in order to determine the accounting treatment for debt issuance costs related to the debt modification. If the evaluation results in a gain (loss) on extinguishment of debt, the amount would be included in Facility fees and debt-related income (expense) on the Consolidated Statements of Operations. If the evaluation results in a modification of debt, unamortized costs would be amortized over the new contractual term. 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. Total revenues include service revenues from the Company's HE, CE and Rail segments and product revenues from the Company's HE and Rail segments. Harsco Environmental - HE provides on-site services, under long-term contracts which may contain multiple performance obligations for material logistics, product quality improvement and resource recovery from iron, steel and metals manufacturing, and the production of aluminum dross and scrap processing systems. • 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, including 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, which is typically 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. • Product revenues in the aluminum dross and scrap process systems business are generally recognized over time as control is transferred to the customer. Control transfers over time because aluminum dross and scrap systems 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 ("cost-to-cost method") 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. Clean Earth - This Segment provides specialty waste processing and beneficial reuse solutions for hazardous wastes, and soil and dredged materials. • 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 the amount of materials received for processing 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 principally variable based on volume and recognized as services are performed. Amounts are typically billed and payable on a monthly basis. Harsco Rail - This business sells railway track maintenance equipment, after-market parts and safety and diagnostic equipment and provides railway track maintenance services. Certain contracts may contain multiple performance obligations, such as a sale of equipment with services and spare parts. • For standard 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. Rail uses the cost-to-cost method to measure progress because it is the measure that best depicts the transfer of control to the customer, which occurs as costs are incurred under the contracts. Under the cost-to-cost method, the extent of progress towards completion is based on the ratio of costs incurred to total estimated costs at completion, which includes both actual costs already incurred and the estimated costs to complete. Accounting for contracts with customers using the cost-to-cost method requires significant judgment relative to assessing risks, which may include estimating contract revenues (including estimates of variable consideration, if applicable, as well as estimating any liquidating damages or penalties related to performance), estimating contract costs (including estimating engineering costs to design the machine and the material, labor and overhead manufacturing costs to build the machine), making assumptions for schedule and technical items, properly executing the engineering and design phases consistent with customer expectations; the availability and costs of labor and material resources, productivity and evaluating whether a significant financing component is present. Due to the number of years it may take to complete certain contracts and the scope and nature of the work required to be performed on those contracts, estimating total revenues and costs at completion is inherently complicated and subject to many variables. 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. Railway track maintenance equipment revenue of approximately $48.5 million, $70.9 million and $49.6 million was recognized using the cost-to-cost method in 2024, 2023, and 2022, respectively. • For after-market parts sales and safety and diagnostics equipment, revenue is recognized at the point when control transfers to the customer. Control generally transfers 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, including footage, 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. The Company has elected to utilize the following practical expedients on an ongoing basis: • 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 in Note 17, Revenue Recognition is limited to the fixed portion of fees related to revenues from services and products in HE and Rail. Taxes assessed by governmental authorities that are both imposed on and concurrent with a specific revenue-producing transaction, that are collected by the Company from a customer, are excluded from revenue. Additionally, in certain contracts, the Company facilitates shipping and handling activities after control has transferred to the customer. The Company has elected to record all shipping and handling activities as costs to fulfill a contract. In situations where the shipping and handling costs have not been incurred at the time revenue is recognized, the respective shipping and handling costs are accrued. Income Taxes The Company accounts for income taxes under the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of the events that have been included in the consolidated financial statements. Under this method, deferred tax assets and liabilities are determined based on the differences between the consolidated financial statements and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in income in the period that includes the enactment date. The Company records deferred tax assets to the extent that the Company believes that these assets will more likely than not be realized. In making such determinations, the Company considers all available positive and negative evidence, including future reversals of existing deferred tax liabilities, projected future taxable income, tax planning strategies and recent financial results. If the Company determines that it will not be able to realize deferred income tax assets in the future, a valuation allowance is recorded. If sufficient positive evidence arises in the future indicating that all or a portion of the deferred tax assets meet the more likely than not standard for realization, the valuation allowance would be reduced accordingly in the period that such a conclusion is reached. The Company prepares and files tax returns based on interpretation of tax laws and regulations and records its provision for income taxes based on these interpretations. Uncertainties may exist in estimating the Company's tax provisions and in filing tax returns in the many jurisdictions in which the Company operates, and as a result these interpretations may give rise to an uncertain tax position. The tax benefit from an uncertain tax position is recognized when it is more likely than not that the position will be sustained upon examination, including resolutions of any related appeals or litigation processes, based on its technical merits. Each subsequent period, the Company determines if existing or new uncertain tax positions meet a more likely than not recognition threshold and adjusts accordingly. The Company recognizes interest and penalties related to unrecognized tax benefits within Income tax expense in the accompanying Consolidated Statements of Operations. Liabilities for uncertain tax positions are included in Other liabilities on the Consolidated Balance Sheets. The significant assumptions and estimates described in the preceding paragraphs are important contributors to the effective tax rate each year. See Note 11, Income Taxes Accrued Insurance and Loss Reserves The Company retains a significant portion of the risk for certain U.S. workers' compensation, U.K. employers' liability, automobile, general and product liability losses. Insurance reserves have been recorded that reflect the undiscounted estimated liabilities including claims incurred but not reported. When a recognized liability is covered by third-party insurance, the Company records an insurance claim receivable to reflect the covered liability. Changes in the estimates of the reserves are included in net income (loss) in the period determined. During the years ended December 31, 2024, 2023 and 2022, the Company recorded insurance reserve adjustments that increased (decreased) pre-tax insurance expense from continuing operations for self-insured programs by $(1.1) million $1.6 million and $(1.6) million, respectively. At December 31, 2024 and 2023, the Company has recorded liabilities of $30.3 million and $32.5 million, respectively, related to both asserted as well as unasserted insurance claims. Included in the balances at December 31, 2024 and 2023 were $5.9 million and $6.5 million, respectively, of recognized liabilities covered by insurance carriers. Amounts estimated to be paid within one year have been included in Other current liabilities, with the remainder included in Other liabilities on the Company's Consolidated Balance Sheets. Foreign Currency Translation The financial statements of the Company's subsidiaries outside the U.S., except for Egypt, Turkey and Argentina which are located in highly inflationary economies and those entities for which the U.S. dollar is the functional currency, are measured using the local currency as the functional currency. Assets and liabilities of these subsidiaries are translated at the exchange rates at the balance sheet date. Resulting translation adjustments are recorded in the cumulative translation adjustment account, a separate component of AOCI, on the Consolidated Balance Sheets. Income and expense items are translated at average monthly exchange rates. Gains and losses from foreign currency transactions are included in Operating income from continuing operations. For subsidiaries operating in highly inflationary economies, and those entities for which the U.S. dollar is the currency of the primary economic environment in which the entity operates, gains and losses on foreign currency transactions and balance sheet translation adjustments are included in Operating income from continuing operations. Financial Instruments and Hedging The Company has operations throughout the world that are exposed to fluctuations in related foreign currencies in the normal course of business. The Company seeks to reduce exposure to foreign currency fluctuations through the use of forward exchange contracts. The Company does not hold or issue financial instruments for trading purposes, and it is the Company's policy to prohibit the use of derivatives for speculative purposes. The Company has a Foreign Currency Risk Management Committee that meets periodically to monitor foreign currency risks. The Company executes foreign currency exchange forward contracts to hedge transactions for firm purchase commitments, to hedge variable cash flows of forecasted transactions and for export sales denominated in foreign currencies. These contracts are generally for 90 days or less; however, where appropriate, longer-term contracts may be utilized. For those contracts that are designated as qualified cash flow hedges, gains or losses are recorded in AOCI on the Consolidated Balance Sheets. The Company uses interest rate swaps in conjunction with certain debt issuances in order to secure a fixed interest rate. The interest rate swaps are recorded on the Consolidated Balance Sheets at fair value, with changes in value attributed to the effect of the swaps’ interest spread and changes in the credit worthiness of the counter-parties recorded in AOCI. Amounts recorded in AOCI on the Consolidated Balance Sheets are reclassified into income in the same period or periods during which the hedged forecasted transaction affects income. The cash flows from these contracts are classified consistent with the cash flows from the transaction being hedged (e.g., the cash flows related to contracts to hedge the purchase of fixed assets are included in cash flows from investing activities, etc.). The Company also enters into certain forward exchange contracts that are not designated as hedges. Gains and losses on these contracts are recognized in the Consolidated Statements of Operations based on changes in fair market value. For fair value hedges of a firm commitment, the gain or loss on the derivative and the offsetting gain or loss on the hedged firm commitment are recognized concurrently in the Consolidated Statements of Operations. See Note 15, Financial Instruments Earnings Per Share Basic earnings per share are calculated using the weighted-average shares of common stock outstanding, while diluted earnings per share reflect the dilutive effects of stock-based compensation. Dilutive

Recently Adopted and Recently I

Recently Adopted and Recently Issued Accounting Standards	12 Months Ended
	Dec. 31, 2024
Accounting Changes and Error Corrections [Abstract]
Recently Adopted and Recently Issued Accounting Standards	Recently Adopted and Recently Issued Accounting Standards The following accounting standards were adopted in 2024: For the year ended December 31, 2024, the Company adopted changes issued by the FASB that require expansion of annual and interim disclosure requirements for reportable segments. The changes require additional interim and annual disclosures regarding segment profit (loss) measures that are regularly reviewed by the chief operating decision maker, which include significant segment expenses and other segment items that are included in the reported segment profit (loss), segment asset information and a reconciliation of the reportable segment amounts for each profit (loss) measure to the corresponding amounts on an entity's consolidated financial statements. This change also requires additional annual disclosures for other qualitative information related to the chief operating decision maker and how the reported measures are used by him. The adoption of these changes did not have any material impact on the Company's Consolidated Financial Statements. See Note 16, Information by Segment and Geographic Area for details. The following accounting standards have been issued and become effective for the Company at a future date: In December 2023, the FASB issued changes which require greater disaggregation of income tax disclosures related to the income tax rate reconciliation and income taxes paid. The changes become effective starting with the Company's annual financial statements for the year ended December 31, 2025. The guidance should be applied on a prospective basis with the option to apply the standard retrospectively. Early adoption is permitted. The Company is currently evaluating the impact that this change will have on the Company's disclosures. In November 2024, the FASB issued changes which requires disaggregated disclosure of income statement expenses within the footnotes to the financial statement for each interim and annual reporting period. The changes become effective starting with the Company's annual financial statements for the year ended December 31, 2027 and will be in effect for the Company's interim financial statements after December 31, 2027. The guidance should be applied on a prospective basis with the option to apply the standard retrospectively. Early adoption is permitted. The Company is currently evaluating the impact that this change will have on the Company's disclosures.

Discontinued Operations

Discontinued Operations	12 Months Ended
	Dec. 31, 2024
Business Combinations [Abstract]
Acquisitions and Dispositions	Discontinued Operations and Dispositions Harsco Rail Segment The results of the Rail business were previously presented as discontinued operations for the periods including November 2021 through February 2024. However, the held for sale criteria were no longer met beginning with March 31, 2024 as the sales process has been paused. The assets and liabilities of the Rail business, previously presented as held for sale, were reclassified to held and used in the Consolidated Balance Sheets as of December 31, 2023, and the results of the Rail business were reclassified from discontinued operations to continuing operations for all periods presented in the Consolidated Statements of Operations. The Rail business’ assets and liabilities as of March 31, 2024 were measured at the carrying amount before the assets were classified as held for sale, reduced $10.7 million by representing the depreciation and amortization expense that would have been recognized had the assets been continuously classified as held for use. The $10.7 million reduction to the carrying value of the Rail assets was reported in Remeasurement of long-lived assets in the Consolidated Statements of Operations in the first quarter of 2024. The reclassification of the Rail business's balance sheet positions as of December 31, 2023 had the following impacts on the Consolidated Balance Sheets and are summarized as follows: (in thousands) December 31 Trade accounts receivable, net $ 57,415 Other receivables 6,708 Inventories 103,077 Current portion of contract assets 56,341 Prepaid expenses 28,797 Other current assets 2,895 Property, plant and equipment, net 44,113 Right-of-use assets, net 7,050 Goodwill 13,026 Intangible assets, net 3,122 Retirement plan assets 344 Deferred income tax assets 973 Other assets 22,448 Total assets $ 346,309 Accounts payable $ 44,703 Accrued compensation 6,056 Income taxes payable 1,434 Current portion of operating lease liabilities 3,656 Current portion of advances on contracts 32,912 Reserve for contracts 52,725 Other current liabilities 30,550 Operating lease liabilities 3,331 Deferred tax liabilities 350 Other liabilities 494 Total liabilities $ 176,211 The reclassification of the results of the Rail business to continuing operations had the following impacts on the Consolidated Statement of Operations for the years ended December 31, 2023 and 2022: Years Ended December 31 (In thousands) 2023 2022 Service revenues $ 52,430 $ 29,331 Product revenues 244,365 215,585 Total revenues 296,795 244,916 Cost of services sold 34,552 19,550 Cost of products sold 247,917 223,034 Total cost of sales 282,469 242,584 Selling, general and administrative expenses 41,602 36,799 Research and development expenses 2,172 2,168 Other expense (income) net 1,628 6,917 Total costs and expenses 327,871 288,468 Operating income (loss) from continuing operations (31,076) (43,552) Interest income 139 270 Interest expense (3,209) (1,651) Defined benefit pension income (expense) 26 (5) Income (loss) from continuing operations before taxes and equity income (34,120) (44,938) Income tax benefit (expense) from continuing operations (2,681) 5,525 Income (loss) from continuing operations $ (36,801) $ (39,413) Harsco Environmental Segment On April 1, 2024, the Company completed the sale of Performix, a subsidiary of HE, for $17.5 million, subject to normal post-closing adjustments, and recognized a gain on the sale of $1.8 million (or approximately $1.3 million after-tax). The most material classes of assets on the date of the sale were Accounts receivable of $4.7 million and Goodwill of $5.3 million. On August 29, 2024, the Company completed the sale of Reed, a subsidiary of HE, for $45.0 million subject to normal post-closing adjustments, and recognized a gain on sale of $8.7 million (or approximately $2.8 million after-tax). The most material classes of assets and liabilities on the date of the sale were Trade accounts receivable, net of $9.9 million, Inventories of $7.1 million, Property, plant and equipment ("PP&E") net of $10.7 million, Goodwill of $13.7 million and Accounts payable of $6.9 million. Other

Accounts Receivable and Note Re

Accounts Receivable and Note Receivable (Notes)	12 Months Ended
	Dec. 31, 2024
Receivables [Abstract]
Accounts Receivable and Note Receivable	Accounts receivable consist of the following: (In thousands) December 31 December 31 Trade accounts receivable $ 275,804 $ 353,709 Less: Allowance for expected credit losses (15,114) (15,522) Trade accounts receivable, net $ 260,690 $ 338,187 Other receivables (a) $ 40,439 $ 40,565 (a) Other receivables include employee receivables, insurance receivable, tax claims and refunds and other miscellaneous receivables not included in Trade accounts receivable, net. The provision for expected credit losses related to trade accounts receivable was as follows: Years Ended December 31 (In thousands) 2024 2023 2022 Change in provision for expected credit losses $ 2,821 $ 7,042 $ 330 At December 31, 2024, $9.5 million of the Company's trade accounts receivable were past due by twelve months or more, with $6.5 million of this amount reserved. During the fourth quarter of 2024, a $3.7 million provision was recorded for the full balance of receivables related to an HE site, which was exited due to the recent insolvency of the customer. Accounts Receivable Securitization Facility In June 2022, the Company and its SPE entered into an AR Facility with PNC Bank, National Association ("PNC") to accelerate cash flows from trade accounts receivable. On October 1, 2024, the Company renewed the AR Facility for a three The total outstanding balance of trade receivables that have been sold and derecognized by the SPE is $150.0 million as of December 31, 2024. The SPE owned $63.8 million and $82.2 million of the Company's trade receivables as of December 31, 2024 and 2023, respectively, which are included in the caption Trade accounts receivable, net, on the Consolidated Balance Sheets. In 2022, the Company capitalized fees of $1.8 million related to the AR Facility, which are amortized into Facility fees and debt-related income (expense) on a straight-line basis over the AR Facility term on the Consolidated Statements of Operations. In 2024, the Company capitalized fees of $0.4 million related to the renewal of the AR Facility which will be amortized into Facility fees and debt-related income (expense) over the new term on a straight-line basis. These fees totaled $0.5 million, $0.6 million and $0.3 million for the years ended December 31, 2024, 2023, and 2022, respectively. For the years ended December 31, 2024, 2023, and 2022, the Company incurred fees of $9.5 million, $9.1 million, and $2.9 million, respectively, in association with the AR Facility, which were reflected in Facility fees and debt-related income (expense) in the Consolidated Statements of Operations. Factoring Arrangements The Company maintains factoring arrangements with a financial institution to sell certain accounts receivable that are also accounted for as a sale of financial assets. The following table reflects balances for net amounts sold and program capacities for the arrangements: (In millions) December 31 December 31 Net amounts sold under factoring arrangements $ 13.3 $ 16.1 Program capacities 18.6 32.6 Note Receivable In January 2020, the Company sold IKG for $85.0 million including cash and a note receivable, subject to post-closing adjustments. The note receivable from the buyer has a face value of $40.0 million, bearing interest at 2.50%, that is paid in kind and matures on January 31, 2027. Due to a change in control of the ownership of IKG during the second quarter of 2024, prepayment of the note was required, as defined in the note receivable agreement. As such, the Company received a payment of $17.0 million in 2024, resulting in a pre-tax gain of $2.7 million reflected in the caption Interest income on the Consolidated Statement of Operations. As of December 31, 2023, the balance was classified as noncurrent and is included in the caption Other assets on the Consolidated Balance Sheet at amortized cost. The following table reflects the note receivable at amortized cost and at fair value: (In millions) December 31 December 31 Note receivable, at amortized cost $ — $ 14.0 Note receivable, at fair value — 15.4

Inventories

Inventories	12 Months Ended
	Dec. 31, 2024
Inventory Disclosure [Abstract]
Inventories	Inventories Inventories consist of the following: (In thousands) December 31 December 31 Finished goods $ 14,344 $ 16,171 Work-in-process 15,629 13,081 Raw materials and purchased parts 107,364 114,046 Stores and supplies 44,705 46,071 Total inventories $ 182,042 $ 189,369 Valued at lower of cost or market: LIFO basis $ 96,680 $ 95,203 FIFO basis 18,747 18,685 Average cost basis 66,615 75,481 Total inventories $ 182,042 $ 189,369

Property, Plant and Equipment

Property, Plant and Equipment	12 Months Ended
	Dec. 31, 2024
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	Property, Plant and Equipment, Net PP&E consist of the following: (In thousands) Estimated December 31 December 31 Land and improvements 5-20 years $ 94,551 $ 93,793 Buildings and improvements (a) 10-30 years 225,688 243,472 Machinery and equipment (b) 3-20 years 1,576,298 1,729,637 Uncompleted construction — 53,441 66,241 Gross property, plant and equipment 1,949,978 2,133,143 Less: Accumulated depreciation (1,285,686) (1,425,746) Property, plant and equipment, net $ 664,292 $ 707,397 (a) Buildings and improvements include leasehold improvements that are amortized over the shorter of their useful lives or the term of the lease. (b) Includes information technology hardware and software. In the fourth quarter of 2024, due to lower revenue projections at an HE location in the United States, the Company performed testing which determined that the undiscounted future cash flows were lower than the net book value of the assets at the location. The assets primarily included machinery and equipment along with other PP&E. The Company used a DCF model to estimate the current fair value of the PP&E (Level 3). As a result of this test, the fair value was less than book value and an impairment charge of $13.9 million was recorded, which is included in the caption Property, plant and equipment impairment charge in the Consolidated Statements of Operations. In the fourth quarter of 2024, an impairment charge of $9.5 million was recorded at an HE location in the Middle East due to a change in the expected long-term use of the asset which is included in the caption Property, plant and equipment impairment charge in the Consolidated Statements of Operations. In 2023, the Company recorded an impairment charge of $14.1 million related to abandoned equipment at a customer site of HE China, which is included in the caption Property, plant and equipment impairment charge in the Consolidated Statements of Operations.

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	12 Months Ended
	Dec. 31, 2024
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets	Goodwill and Other Intangible Assets Goodwill by Segment The following table reflects the changes in carrying amounts of goodwill by each reporting unit for the years ended December 31, 2024 and 2023: (In thousands) Harsco Environmental Clean Earth Harsco Rail Consolidated Totals Balance at December 31, 2022 $ 379,954 $ 379,299 $ 13,026 $ 772,279 Foreign currency translation 8,699 — — 8,699 Balance at December 31, 2023 388,653 379,299 13,026 780,978 Changes to goodwill (a) (19,031) — — (19,031) Goodwill impairment — — (13,026) (13,026) Foreign currency translation (9,163) — — (9,163) Balance at December 31, 2024 $ 360,459 $ 379,299 $ — $ 739,758 (a) The changes to goodwill relate to the divestitures of the Performix and Reed businesses. The Company's methodology for determining the fair value for its reporting units is described in Note 1, Summary of Significant Accounting Policies. The Company tests for goodwill impairment annually as of October 1, or more frequently if indicators of impairment exist or a decision is made to dispose of a business. The performance of the Company's 2024 annual quantitative impairment tests did not result in impairment of the Company's goodwill for Harsco Environmental or Clean Earth. See Note 1 , Summary of Significant Accounting Policies , for the Company's methodol o gy for determining repor ting unit fair value. In 2022, as a result of lower earnings expectations due to the impacts of inflation, an interim goodwill test was required for the Clean Earth reporting unit. As a result of this testing, the Company recorded a goodwill impairment charge of $104.6 million, which is included in Goodwill and other intangible asset impairment charges on the Consolidated Statement of Operations for the year-ended December 31, 2022. Intangible Assets Net intangible assets totaled $298.4 million and $328.0 million at December 31, 2024 and 2023, respectively. The following table reflects these intangible assets by major category: December 31, 2024 December 31, 2023 (In thousands) Gross Carrying Accumulated Gross Carrying Accumulated Customer related $ 95,251 $ 69,795 $ 102,119 $ 66,016 Permits 310,236 82,799 309,679 66,733 Technology related 22,880 17,477 21,803 17,001 Trade names 31,514 15,142 31,580 12,428 Air rights 26,139 3,979 26,139 3,281 Patents 162 148 206 179 Non-compete agreement 2,500 2,500 2,500 2,343 Other 3,457 1,861 3,584 1,646 Total $ 492,139 $ 193,701 $ 497,610 $ 169,627 In 2024, due to the loss of a customer in Europe for HE, the Company recorded a $2.8 million charge to fully impair the value of a related customer relationship intangible asset, which is included in Goodwill and other intangible asset impairment charges on the Consolidated Statement of Operations. In 2022, based on the current economic conditions, to include inflation and higher energy prices, the Company lowered its long-range projections for the Altek Group of the Harsco Environmental Segment and therefore tested the recoverability of Altek's asset group. As a result of this testing, an impairment charge of $15.0 million was recorded, which is included in Goodwill and other intangible asset impairment charges on the Consolidated Statements of Operations for the year-ended December 31, 2022. The carrying value of Altek's intangible assets after the impairment charge was $15.3 million at December 31, 2022. Amortization expense for intangible assets was $27.3 million, $28.9 million and $31.4 million for 2024, 2023 and 2022, respectively. Intangible assets are principally amortized using the straight-line method over the estimated useful life, except for the air rights, which are amortized based on usage. The following table shows the estimated amortization expense for the next five fiscal years based on current intangible assets. (In thousands) 2025 2026 2027 2028 2029 Estimated amortization expense (a) $ 26,300 $ 26,300 $ 25,000 $ 23,500 $ 22,800 (a) These estimated amortization expense amounts do not reflect the potential effect of future foreign currency exchange rate fluctuations.

Debt and Credit Agreements

Debt and Credit Agreements	12 Months Ended
	Dec. 31, 2024
Debt Disclosure [Abstract]
Debt and Credit Agreements	Debt and Credit Agreements The Company's long-term debt consists of the following: (In thousands) December 31 December 31 Senior Secured Credit Facilities (a) : Term Loan with an interest rate of 6.72% and 7.72% at December 31, 2024 and 2023, respectively $ 482,500 $ 487,500 Revolving Credit Facility with an average interest rate of 6.49% and 8.12% at December 31, 2024 and 2023, respectively 407,000 422,000 5.75% Senior Notes 475,000 475,000 Other financing payable (including finance leases) in varying amounts due principally through 2030 with a weighted-average interest rate of 7.14% and 6.11% at December 31, 2024 and 2023, respectively 79,917 44,469 Total debt obligations 1,444,417 1,428,969 Less: deferred financing costs (12,695) (11,974) Total debt obligations, net of deferred financing costs 1,431,722 1,416,995 Less: current maturities of long-term debt (21,004) (15,558) Long-term debt $ 1,410,718 $ 1,401,437 (a) The current portion of long-term debt related to the Senior Secured Credit Facilities was $5.0 million with the remainder reflected as Long-term debt at December 31, 2024 and 2023. The maturities of long-term debt for the four years following December 31, 2025 are as follows: (In thousands) 2026 $ 50,019 2027 494,421 2028 480,873 2029 387,026 Cash payments for interest on debt were $109.5 million, $101.5 million and $73.4 million in 2024, 2023 and 2022, respectively. On February 14, 2025, the Company entered into an amendment to the credit agreement to reset the levels of its covenants, among other changes. The Company obtained the amendment because its forward-looking projections indicated that it may not meet the minimum level required by the interest coverage ratio. As a result of this amendment, the total Net Debt to Consolidated Adjusted EBITDA ratio covenant was set to 4.75x for the quarters ended December 31, 2024 and March 31, 2025, 5.00x for the quarters ended June 30, 2025 and September 30, 2025, and then decreases every six months by 0.25x until reaching 4.00x for the quarter ended June 30, 2027 and thereafter. The interest coverage ratio was set at 2.75x for the quarter ended December 31, 2024 and 2.50x for each quarter after. The Company continues to expect that it will continue to maintain compliance with the amended covenants. In September 2024, the Company amended its Senior Secured Credit Facilities to, among other things, extend the term of the Revolving Credit Facility to September 5, 2029 and adjust the limit to $625.0 million. In addition, the Company retained $50.0 million of its existing revolving commitments which mature on March 10, 2026. The extended Revolving Credit Facility bears interest at a rate, depending on total net leverage, ranging from 75 to 125 basis points over base rate or 175 to 225 basis points over SOFR and the existing Revolving Credit Facility bears interest at a rate, depending on total net leverage, ranging from 50 to 175 basis points over base rate or 150 to 275 basis points over SOFR, in each case, subject to zero floor. The Company expensed $0.3 million of previously recorded deferred financing costs and capitalized $4.4 million of fees incurred related to the amendment. Also as a result of this amendment, the net debt to consolidated adjusted EBITDA ratio covenant is 4.75x for the quarter ended September 30, 2024, and decreases to 4.50x for the quarter ended June 30, 2025, 4.25x for the quarter ended December 31, 2025 and 4.00x thereafter. The Company's required coverage of consolidated interest charges is set at a minimum of 2.75x through the end of 2024 and increases to 3.00x beginning with the first quarter of 2025. At December 31, 2024, the Company was in compliance with all covenants for its Senior Secured Credit Facilities, as amended in February 2025, as the total Net Debt to Consolidated Adjusted EBITDA ratio was 4.07x and the total interest coverage ratio was 3.05x. Based on balances and covenants in effect at December 31, 2024, the Company could increase Net Debt by $227.6 million and still be in compliance with these debt covenants. Alternatively, Consolidated Adjusted EBITDA could decrease by $33.1 million or interest expense could increase by $12.1 million and the Company would remain in compliance with these covenants. The Company believes it will continue to maintain compliance with these amended covenants based on its current outlook. However, the Company's estimates of compliance with these covenants could change in the future with a deterioration in economic conditions, higher than forecasted interest rates, the timing of working capital including the collection of receivables, an inability to realize increased pricing and implement cost reduction initiatives, principally in CE, that mitigate the impacts of inflation and other factors that may adversely impact its compliance with covenants. The Company's Credit Agreement imposes certain restrictions including, but not limited to, restrictions as to types and amounts of debt of liens that may be incurred by the Company; limitations on increases in dividend payments; limitations on repurchases of the Company's stock and limitations on certain acquisitions by the Company. With respect to the Senior Secured Credit Facilities, the obligations of the Company are guaranteed by substantially all of the Company’s current and future wholly-owned domestic subsidiaries (“Guarantors”). All obligations under the Senior Credit Facility, and the guarantees of those obligations, are secured, subject to certain exceptions, by substantially all of the Company’s assets and the assets of the Guarantors. The Credit Agreement requires certain mandatory prepayments of the Term Loan, subject to certain exceptions, based on net cash proceeds of certain sales or distributions of assets, as well as certain casualty and condemnation events, in some cases subject to reinvestment rights and certain other exceptions; net cash proceeds of any issuance of debt, excluding permitted debt issuances; and a percentage of excess cash flow, as defined by the Credit Agreement, during a fiscal year. Facility Fees and Debt-Related Income (Expense) The components of the Consolidated Statements of Operations caption Facility fees and debt-related income (expense) were as follows: Years Ended December 31 (In thousands) 2024 2023 2022 Gain (loss) on extinguishment of debt $ (325) $ — $ 2,254 Unused debt commitment and amendment fees — (12) (1,696) Securitization and factoring fees (10,940) (10,750) (3,514) Facility fees and debt-related income (expense) $ (11,265) $ (10,762) $ (2,956) Revolving Credit Facility The following table shows the amount outstanding under the Revolving Credit Facility and available credit at December 31, 2024. December 31, 2024 (In thousands) Facility Outstanding Outstanding Letters of Credit Available Revolving Credit Facility $ 675,000 $ 407,000 $ 29,846 $ 238,154 Other

Leases

Leases	12 Months Ended
	Dec. 31, 2024
Leases [Abstract]
Leases	Leases The components of lease expense were as follows: (In thousands) 2024 2023 2022 Finance leases: Depreciation expense $ 12,785 $ 7,957 $ 3,938 Interest on lease liabilities 4,318 2,036 784 Operating leases 38,702 38,062 35,290 Variable and short-term leases 54,475 54,432 52,050 Sublease income (7) (7) (6) Total lease expense $ 110,273 $ 102,480 $ 92,056 Supplemental cash flow information related to leases was as follows: (In thousands) 2024 2023 2022 Cash paid for amounts included in the measurement of lease liabilities: Cash flows used by operating activities - Operating leases $ 37,120 $ 37,880 $ 34,420 Cash flows used by operating activities - Finance leases 4,203 1,914 798 Cash flows used by financing activities - Finance leases 12,316 7,736 3,975 ROU assets obtained in exchange for lease obligations: Operating leases $ 21,895 $ 27,951 $ 32,817 Finance leases 49,316 27,128 11,175 Supplemental balance sheet information related to leases was as follows: (In thousands) 2024 2023 Operating Leases: Operating lease ROU assets $ 92,153 $ 102,891 Current portion of operating lease liabilities 26,049 28,775 Operating lease liabilities 67,998 75,476 Finance Leases: Property, plant and equipment, net $ 73,734 $ 43,151 Current maturities of long-term debt 16,004 9,723 Long-term debt 63,913 33,911 Supplemental additional information related to leases was as follows: 2024 2023 Other information: Weighted average remaining lease term - Operating leases (in years) 6.98 7.03 Weighted average remaining lease term - Finance leases (in years) 5.27 5.33 Weighted average incremental borrowing rate - Operating leases 6.7 % 6.3 % Weighted average incremental borrowing rate - Finance leases 7.2 % 6.4 % Maturities of lease liabilities were as follows: (In thousands) Operating Leases Finance Leases Year Ending December 31: 2025 $ 32,934 $ 20,998 2026 25,516 19,462 2027 18,456 17,488 2028 12,803 15,525 2029 8,724 10,938 After 2029 41,883 11,805 Total lease payments 140,316 96,216 Less: Imputed interest (32,030) (16,299) Total lease liabilities (a) $ 108,286 $ 79,917 (a) Includes payments for operating leases of approximately $14 million related to fully executed renewal agreements for building leases that will go into effect starting in 2025. The Company's leases, excluding short-term leases, have remaining terms of less than one year to approximately 26 years, some of which contain options to extend or terminate the lease terms, based on the provisions in the lease agreements. As of December 31, 2024, the Company has approximately $27 million of finance lease obligations to be recognized for vehicles and equipment in CE with expected commencement dates in 2025. There are no material residual value guarantees or material restrictive covenants in any of the Company's leases.
Leases	Leases The components of lease expense were as follows: (In thousands) 2024 2023 2022 Finance leases: Depreciation expense $ 12,785 $ 7,957 $ 3,938 Interest on lease liabilities 4,318 2,036 784 Operating leases 38,702 38,062 35,290 Variable and short-term leases 54,475 54,432 52,050 Sublease income (7) (7) (6) Total lease expense $ 110,273 $ 102,480 $ 92,056 Supplemental cash flow information related to leases was as follows: (In thousands) 2024 2023 2022 Cash paid for amounts included in the measurement of lease liabilities: Cash flows used by operating activities - Operating leases $ 37,120 $ 37,880 $ 34,420 Cash flows used by operating activities - Finance leases 4,203 1,914 798 Cash flows used by financing activities - Finance leases 12,316 7,736 3,975 ROU assets obtained in exchange for lease obligations: Operating leases $ 21,895 $ 27,951 $ 32,817 Finance leases 49,316 27,128 11,175 Supplemental balance sheet information related to leases was as follows: (In thousands) 2024 2023 Operating Leases: Operating lease ROU assets $ 92,153 $ 102,891 Current portion of operating lease liabilities 26,049 28,775 Operating lease liabilities 67,998 75,476 Finance Leases: Property, plant and equipment, net $ 73,734 $ 43,151 Current maturities of long-term debt 16,004 9,723 Long-term debt 63,913 33,911 Supplemental additional information related to leases was as follows: 2024 2023 Other information: Weighted average remaining lease term - Operating leases (in years) 6.98 7.03 Weighted average remaining lease term - Finance leases (in years) 5.27 5.33 Weighted average incremental borrowing rate - Operating leases 6.7 % 6.3 % Weighted average incremental borrowing rate - Finance leases 7.2 % 6.4 % Maturities of lease liabilities were as follows: (In thousands) Operating Leases Finance Leases Year Ending December 31: 2025 $ 32,934 $ 20,998 2026 25,516 19,462 2027 18,456 17,488 2028 12,803 15,525 2029 8,724 10,938 After 2029 41,883 11,805 Total lease payments 140,316 96,216 Less: Imputed interest (32,030) (16,299) Total lease liabilities (a) $ 108,286 $ 79,917 (a) Includes payments for operating leases of approximately $14 million related to fully executed renewal agreements for building leases that will go into effect starting in 2025. The Company's leases, excluding short-term leases, have remaining terms of less than one year to approximately 26 years, some of which contain options to extend or terminate the lease terms, based on the provisions in the lease agreements. As of December 31, 2024, the Company has approximately $27 million of finance lease obligations to be recognized for vehicles and equipment in CE with expected commencement dates in 2025. There are no material residual value guarantees or material restrictive covenants in any of the Company's leases.
Leases	Leases The components of lease expense were as follows: (In thousands) 2024 2023 2022 Finance leases: Depreciation expense $ 12,785 $ 7,957 $ 3,938 Interest on lease liabilities 4,318 2,036 784 Operating leases 38,702 38,062 35,290 Variable and short-term leases 54,475 54,432 52,050 Sublease income (7) (7) (6) Total lease expense $ 110,273 $ 102,480 $ 92,056 Supplemental cash flow information related to leases was as follows: (In thousands) 2024 2023 2022 Cash paid for amounts included in the measurement of lease liabilities: Cash flows used by operating activities - Operating leases $ 37,120 $ 37,880 $ 34,420 Cash flows used by operating activities - Finance leases 4,203 1,914 798 Cash flows used by financing activities - Finance leases 12,316 7,736 3,975 ROU assets obtained in exchange for lease obligations: Operating leases $ 21,895 $ 27,951 $ 32,817 Finance leases 49,316 27,128 11,175 Supplemental balance sheet information related to leases was as follows: (In thousands) 2024 2023 Operating Leases: Operating lease ROU assets $ 92,153 $ 102,891 Current portion of operating lease liabilities 26,049 28,775 Operating lease liabilities 67,998 75,476 Finance Leases: Property, plant and equipment, net $ 73,734 $ 43,151 Current maturities of long-term debt 16,004 9,723 Long-term debt 63,913 33,911 Supplemental additional information related to leases was as follows: 2024 2023 Other information: Weighted average remaining lease term - Operating leases (in years) 6.98 7.03 Weighted average remaining lease term - Finance leases (in years) 5.27 5.33 Weighted average incremental borrowing rate - Operating leases 6.7 % 6.3 % Weighted average incremental borrowing rate - Finance leases 7.2 % 6.4 % Maturities of lease liabilities were as follows: (In thousands) Operating Leases Finance Leases Year Ending December 31: 2025 $ 32,934 $ 20,998 2026 25,516 19,462 2027 18,456 17,488 2028 12,803 15,525 2029 8,724 10,938 After 2029 41,883 11,805 Total lease payments 140,316 96,216 Less: Imputed interest (32,030) (16,299) Total lease liabilities (a) $ 108,286 $ 79,917 (a) Includes payments for operating leases of approximately $14 million related to fully executed renewal agreements for building leases that will go into effect starting in 2025. The Company's leases, excluding short-term leases, have remaining terms of less than one year to approximately 26 years, some of which contain options to extend or terminate the lease terms, based on the provisions in the lease agreements. As of December 31, 2024, the Company has approximately $27 million of finance lease obligations to be recognized for vehicles and equipment in CE with expected commencement dates in 2025. There are no material residual value guarantees or material restrictive covenants in any of the Company's leases.

Employee Benefit Plans

Employee Benefit Plans	12 Months Ended
	Dec. 31, 2024
Retirement Benefits [Abstract]
Employee Benefit Plans	Employee Benefit Plans Pension Benefits The Company has defined benefit pension plans covering a certain number of employees. The defined benefits for salaried employees generally are based on years of service and the employee's level of compensation during specified periods of employment. Defined benefit pension plans covering hourly employees generally provide benefits of stated amounts for each year of service. MEPPs in which the Company participates provide benefits to certain unionized employees. The Company's funding policy for qualified plans is consistent with statutory requirements. Periodic voluntary contributions are made, as recommended, by the Company's Pension Committee. Accrued service is no longer granted to the U.S. defined benefit pension plans and a majority of international defined benefit pension plans due to the plans being frozen. In place of these plans, the Company has established defined contribution plans providing for the Company to contribute a specified matching amount for participating employees' contributions to the plan. For U.S. employees, this match is made on employee contributions up to 4% of eligible compensation. Additionally, the Company may provide a discretionary contribution for eligible employees. There have been no discretionary contributions provided for the years 2024, 2023 and 2022. For non-U.S. employees, this match is up to 6% of eligible compensation with an additional 2% going towards insurance and administrative costs. Changes in the discount rate assumption and the actual performance of plan assets, compared with the expected long-term rate of return on plan assets, are the primary drivers in the change in funded status of the Company's defined benefit pension plans. These factors are components of actuarial loss (gain) and impact the amount recognized in AOCI, as such actuarial changes are not reflected directly on the Consolidated Statements of Operations but amortized over time as permitted by U.S. GAAP. NPPC for U.S. and international plans for 2024, 2023 and 2022 is as follows: U.S. Plans International Plans (In thousands) 2024 2023 2022 2024 2023 2022 Net Periodic Pension Cost (Income): Defined benefit pension plans: Service cost $ — $ — $ — $ 1,322 $ 1,245 $ 2,029 Interest cost 9,676 10,173 5,716 29,409 30,220 16,637 Expected return on plan assets (8,944) (7,000) (10,795) (33,049) (31,281) (39,179) Recognized prior service costs — — — 492 520 534 Recognized losses 4,179 4,601 4,732 15,060 14,316 13,060 Settlement/curtailment loss (gain) — — — (1,125) (42) (33) Defined benefit pension plan cost (income) 4,911 7,774 (347) 12,109 14,978 (6,952) Multiemployer pension plans 570 595 642 1,241 1,209 1,114 Defined contribution plans 9,985 8,468 7,082 5,690 5,396 5,111 Net periodic pension cost (income) $ 15,466 $ 16,837 $ 7,377 $ 19,040 $ 21,583 $ (727) The change in the financial status of the defined benefit pension plans and amounts recognized on the Consolidated Balance Sheets at December 31, 2024 and 2023 are as follows: U.S. Plans International Plans (In thousands) 2024 2023 2024 2023 Change in benefit obligation: Benefit obligation at beginning of year $ 209,177 $ 209,182 $ 642,648 $ 598,302 Service cost — — 1,322 1,245 Interest cost 9,676 10,173 29,409 30,220 Plan participants' contributions — — 12 13 Amendments — — — 74 Actuarial (gain) loss (17,591) 5,736 (57,451) 17,896 Settlements/curtailments — — (1,363) (203) Benefits paid (14,867) (15,914) (36,691) (36,705) Effect of foreign currency — — (15,803) 31,806 Benefit obligation at end of year $ 186,395 $ 209,177 $ 562,083 $ 642,648 Change in plan assets: Fair value of plan assets at beginning of year $ 180,927 $ 177,044 $ 669,021 $ 608,672 Actual return on plan assets 9,931 18,123 (20,357) 40,587 Employer contributions 7,301 1,674 14,778 24,715 Plan participants' contributions — — 12 13 Settlements/curtailments — — (192) (203) Benefits paid (14,867) (15,914) (36,691) (36,705) Effect of foreign currency — — (14,904) 31,942 Fair value of plan assets at end of year $ 183,292 $ 180,927 $ 611,667 $ 669,021 Funded status at end of year $ (3,103) $ (28,250) $ 49,584 $ 26,373 Significant items impacting actuarial gains and losses for 2024 for U.S. plans included the actual return on the fair value of plan assets since the prior measurement date was greater than assumed, which caused the funded position to improve; an increase in the discount rate used to measure the benefit obligation compared with the prior year, which caused the funded position to improve; and actuarial gains resulting from demographic changes such as mortality, which improved the funded position. Significant items impacting actuarial gains and losses for 2024 for U.K. plans included an increase in the discount rate used to measure the benefit obligation compared with the prior year, which caused the funded position to improve; and the actual return on the fair value of plan assets since the prior measurement date was less than assumed, which caused the funded position to deteriorate. Amounts recognized on the Consolidated Balance Sheets for defined benefit pension plans consist of the following at December 31, 2024 and 2023: U.S. Plans International Plans December 31 December 31 (In thousands) 2024 2023 2024 2023 Noncurrent assets $ 9,917 $ — $ 63,879 $ 44,585 Current liabilities 1,713 1,832 507 726 Noncurrent liabilities 11,307 26,418 13,788 17,486 AOCI 72,260 95,016 332,026 358,631 Amounts recognized in AOCI for defined benefit pension plans consist of the following at December 31, 2024 and 2023: U.S. Plans International Plans (In thousands) 2024 2023 2024 2023 Net actuarial loss $ 72,260 $ 95,016 $ 324,661 $ 350,469 Prior service cost — — 7,365 8,162 Total $ 72,260 $ 95,016 $ 332,026 $ 358,631 The Company's estimate of expected contributions to be paid in 2025 for the U.S. and international defined benefit plans total $3.0 million and $0.8 million, respectively. Future Benefit Payments Expected benefit payments for defined benefit pension plans over the next ten years are as follows: (In millions) 2025 2026 2027 2028 2029 2030-2034 U.S. Plans $ 19.7 $ 15.6 $ 15.4 $ 15.2 $ 15.0 $ 71.5 International Plans 36.4 37.0 37.1 38.2 39.5 192.9 Net Periodic Pension Cost and Defined Benefit Pension Obligation Assumptions The weighted-average actuarial assumptions used to determine the defined benefit pension plan NPPC for 2024, 2023 and 2022 were as follows: U.S. Plans International Plans Global Weighted-Average 2024 2023 2022 2024 2023 2022 2024 2023 2022 Discount rates 5.0 % 5.3 % 2.7 % 4.8 % 5.0 % 1.9 % 4.8 % 5.1 % 2.1 % Expected long-term rates of return on plan assets 7.0 % 7.0 % 6.3 % 5.3 % 5.1 % 4.4 % 5.7 % 5.5 % 4.7 % The expected long-term rates of return on defined benefit pension plan assets for the 2025 NPPC are 6.8% for the U.S. plans and 4.6% for the international plans. The expected global long-term rate of return on assets for 2025 is 5.1%. The weighted-average actuarial assumptions used to determine the defined benefit pension plan obligations at December 31, 2024 and 2023 were as follows: U.S. Plans International Plans Global Weighted-Average December 31 December 31 December 31 2024 2023 2024 2023 2024 2023 Discount rates 5.5 % 5.0 % 5.4 % 4.8 % 5.5 % 4.8 % Since accrued service is no longer granted to the U.S. defined benefit plans and the majority of the international defined benefit pension plans, the rate of compensation increase did not have a significant impact on the defined benefit pension obligation at December 31, 2024 and 2023 or the defined benefit pension plan NPPC for the years ended 2024, 2023 and 2022. The U.S. discount rate was determined using a yield curve that was produced from a universe containing approximately 1,100 U.S. dollar-denominated, AA-graded corporate bonds, all of which were noncallable (or callable with make-whole provisions) and excluding the 10% of the bonds with the highest deviation from the expected yield and the 10% with the lowest deviation from the expected yield within each duration group. The discount rate was then developed as the level-equivalent rate that would produce the same present value as that using spot rates to discount the projected benefit payments. For international plans, the discount rate is aligned to corporate bond yields in the local markets, normally AA-rated corporations. The process and selection seek to approximate the cash inflows with the timing and amounts of the expected benefit payments. Accumulated Benefit Obligation The accumulated benefit obligation for all defined benefit pension plans at December 31, 2024 and 2023 was as follows: U.S. Plans International Plans December 31 December 31 (In millions) 2024 2023 2024 2023 Accumulated benefit obligation $ 186.4 $ 209.2 $ 558.4 $ 637.6 Defined Benefit Pension Plans with Accumulated Benefit Obligation in Excess of Plan Assets The projected benefit obligation, accumulated benefit obligation and fair value of plan assets for defined benefit pension plans with accumulated benefit obligations in excess of plan assets at December 31, 2024 and 2023 were as follows: U.S. Plans International Plans December 31 December 31 (In millions) 2024 2023 2024 2023 Projected benefit obligation $ 13.0 $ 209.2 $ 22.1 $ 27.8 Accumulated benefit obligation 13.0 209.2 19.9 24.1 Fair value of plan assets — 180.9 7.9 9.7 At December 31, 2024 and 2023, the asset allocations attributable to the Company's U.S. defined benefit pension plans and the long-term target allocation of plan assets, by asset category, are as follows: Target Long-Term Percentage of Plan Assets U.S. Plans Asset Category 2024 2023 Domestic equity securities 4%-14% 8.8 % 10.7 % International equity securities 17%-27% 21.0 % 24.3 % Fixed income securities 61%-71% 65.4 % 52.8 % Cash and cash equivalents Less than 5% 0.9 % 0.9 % Other (a) 0%-8% 3.9 % 11.3 % (a) Investments within this caption include credit collection funds. Defined benefit pension plan assets are allocated among various categories of equities, fixed income securities and cash and cash equivalents with professional investment managers whose performance is actively monitored. The primary investment objective is to meet present and future benefit obligations through a balanced investment approach to minimize volatility and risk. The Company periodically conducts an asset/liability modeling study and accordingly adjusts investments among and within asset categories to ensure the long-term investment strategy is aligned with the profile of benefit obligations. The Company reviews the long-term expected return on asset assumption on a periodic basis considering a variety of factors including historical investment returns achieved over a long-term period, the targeted allocation of plan assets and future expectations based on a model of asset returns for an actively managed portfolio. The model simulates 1,000 different capital market results over 20 years. The expected return-on-asset assumption for U.S. defined benefit pension plans for 2025 and 2024 is 6.8% and 7.0%, respectively. The U.S. defined benefit pension plans' assets include 310,000 shares at December 31, 2024 and 310,000 shares at December 31, 2023 of the Company's common stock, valued at $2.4 million and $2.8 million, respectively. These shares represented 1.3% and 1.5% of total U.S. plan assets at December 31, 2024 and 2023, respectively. The asset allocations attributable to the Company's international defined benefit pension plans at December 31, 2024 and 2023 and the long-term target allocation of plan assets, by asset category, are as follows: International Plans Asset Category Target Long-Term Percentage of Plan Assets 2024 2023 Equity securities 12.4 % 0.9 % 10.8 % Fixed income securities 82.8 % 95.0 % 83.3 % Cash and cash equivalents — 1.8 % 0.5 % Other (a) 4.8 % 2.3 % 5.4 % (a) Investments within this caption include diversified growth funds and real estate funds. International defined benefit pension plan assets at December 31, 2024 in the U.K. defined benefit pension plan totaled approximately 94% of the international defined benefit pension plan assets. The U.K. plan assets are allocated among various categories of equities, fixed income securities and cash and cash equivalents with professional investment managers whose performance is actively monitored. The primary investment objective is to reduce investment risk and better protect the improved funding position in order to meet present and future benefit obligations. The Company periodically conducts asset/liability modeling studies and accordingly adjusts investment amounts within asset categories to ensure the long-term investment strategy is aligned with the profile of benefit obligations. For the international long-term rate of return assumption, the Company considered the current level of expected returns in risk-free investments (primarily government bonds), the historical level of the risk premium associated with other asset classes in which the portfolio is invested, and the expectations for future returns of each asset class and plan expenses. The expected return for each asset class is then weighted based on the target asset allocation to develop the expected long-term rate of return on assets. The expected return on asset assumption for the U.K. defined benefit pension plan for 2025 and 2024 are 4.6% and 5.3%, respectively. The remaining international defined benefit pension plans, with plan assets representing approximately 6% of the international defined benefit pension plan assets, are under the guidance of professional investment managers and have similar investment objectives. The fair values of the Company's U.S. defined benefit pension plans' assets at December 31, 2024 by asset class are as follows: (In thousands) Total Level 1 Level 2 Investments Valued at Net Asset Value (a) Domestic equities: Common stocks $ 2,388 $ 2,388 $ — $ — Mutual funds—equities 13,748 13,748 — — International equities: Mutual funds—equities 38,398 38,398 — — Fixed income investments: U.S. Treasuries and collateralized securities 15,673 — 15,673 — Mutual funds—bonds 104,166 104,166 — — Cash and money market accounts 1,681 1,681 — — Other—partnerships/joint ventures 7,238 — — 7,238 Total $ 183,292 $ 160,381 $ 15,673 $ 7,238 (a) Certain investments that are measured at fair value using Net Asset Value per share (or its equivalent) as a practical expedient have not been classified in the fair value hierarchy. The fair values of the Company's U.S. defined benefit pension plans' assets at December 31, 2023 by asset class are as follows: (In thousands) Total Level 1 Level 2 Investments Valued at Net Asset Value Domestic equities: Common stocks $ 2,791 $ 2,791 $ — $ — Mutual funds—equities 16,583 16,583 — — International equities: Mutual funds—equities 43,994 43,994 — — Fixed income investments: U.S. Treasuries and collateralized securities 13,920 — 13,920 — Mutual funds—bonds 81,634 81,634 — — Other—mutual funds 4,913 4,913 — — Cash and money market accounts 1,661 1,661 — — Other - partnerships/joint ventures 15,431 — — 15,431 Total $ 180,927 $ 151,576 $ 13,920 $ 15,431 The fair values of the Company's international defined benefit pension plans' assets at December 31, 2024 by asset class are as follows: (In thousands) Total Level 1 Level 2 Equity securities: Mutual funds—equities $ 5,342 $ — $ 5,342 Fixed income investments: Mutual funds—bonds 576,540 — 576,540 Insurance contracts 4,394 — 4,394 Other: Other mutual funds 14,244 — 14,244 Cash and money market accounts 11,147 11,147 — Total $ 611,667 $ 11,147 $ 600,520 The fair values of the Company's international defined benefit pension plans' assets at December 31, 2023 by asset class are as follows: (In thousands) Total Level 1 Level 2 Equity securities: Mutual funds—equities $ 71,980 $ — $ 71,980 Fixed income investments: Mutual funds—bonds 552,898 — 552,898 Insurance contracts 4,631 — 4,631 Other: Other mutual funds 36,263 — 36,263 Cash and money market accounts 3,249 3,249 — Total $ 669,021 $ 3,249 $ 665,772 The following is a description of the valuation methodologies used for the defined benefit pension plans' investments measured at fair value: • Level 1 Fair Value Measurements—Investments in interest-bearing cash are stated at cost, which approximates fair value. The fair values of money market accounts and certain mutual funds are based on quoted net asset values of the shares held by the plan at year-end. The fair values of domestic and international stocks and corporate bonds, notes and convertible debentures are valued at the closing price reported in the active market on which the individual securities are traded. • Level 2 Fair Value Measurements—The fair values of investments in mutual funds for which quoted net asset values in an active market are not available are valued by the investment advisor based on the current market values of the underlying assets of the mutual fund based on information reported by the investment consistent with audited financial statements of the mutual fund. Further information concerning these mutual funds may be obtained from their separate audited financial statements. Investments in U.S. Treasury notes and collateralized securities are valued based on yields currently available on comparable securities of issuers with similar credit ratings. Multiemployer Pension Plans

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2024
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Current income tax expense or benefit represents the amounts expected to be reported on the Company's income tax returns, and deferred income tax expense or benefit represents the change in net deferred tax assets and liabilities. Deferred tax assets and liabilities are determined based on the difference between the financial statement and tax bases of assets and liabilities as measured by the enacted income tax rates that will be in effect when these differences reverse. Valuation allowances are recorded as appropriate to reduce deferred tax assets to the amount considered more likely than not to be realized. Income (loss) from continuing operations before income taxes and equity income as reported on the Consolidated Statements of Operations consists of the following: (In thousands) 2024 2023 2022 U.S. $ (61,205) $ (19,598) $ (171,625) International (40,465) (33,072) 3,728 Total income (loss) from continuing operations before income taxes and equity income $ (101,670) $ (52,670) $ (167,897) Income tax expense (benefit) as reported on the Consolidated Statements of Operations consists of the following: (In thousands) 2024 2023 2022 Income tax expense (benefit): Currently payable: U.S. federal $ 897 $ (823) $ — U.S. state 2,701 3,591 975 International 24,884 23,801 16,428 Total income taxes currently payable 28,482 26,569 17,403 Deferred U.S. federal (5,667) 2,735 (12,655) Deferred U.S. state (2,997) (1,550) (1,935) Deferred international (2,752) 3,112 2,043 Total income tax expense (benefit) from continuing operations $ 17,066 $ 30,866 $ 4,856 Cash payments for income taxes were $29.1 million, $20.1 million and $20.9 million for 2024, 2023 and 2022, respectively. The cash payments for 2024 increased primarily due to the payments for fiscal years 2023 and 2022 in certain foreign jurisdictions and withholding tax on cash repatriations. A reconciliation of the normal expected statutory U.S. federal income tax expense (benefit) to the actual Income tax expense (benefit) from continuing operations as reported on the Consolidated Statements of Operations is as follows: (In thousands) 2024 2023 2022 U.S. federal income tax expense (benefit), at statutory tax rate of 21% $ (21,350) $ (11,060) $ (35,259) U.S. state income taxes, net of federal income tax benefit (1,296) 624 (644) U.S. other domestic deductions and credits (1,084) (1,275) (1,216) Difference in effective tax rates on international earnings and remittances 29,019 26,372 11,166 Uncertain tax position contingencies and settlements (51) (768) (290) Changes in realization of deferred tax assets 10,366 14,498 8,262 U.S. non-deductible expenses 3,663 278 24 Nondeductible goodwill charges 3,676 — 19,548 PP&E / Intangible asset impairment — 2,961 3,150 State deferred tax rate changes (63) 304 343 Foreign derived intangible income deduction (1,675) (2,199) (1,792) Share-based compensation 1,967 1,131 1,564 Capital loss (6,106) — — Total income tax expense (benefit) from continuing operations $ 17,066 $ 30,866 $ 4,856 At December 31, 2024, 2023 and 2022, the Company's annual effective income tax rate on income (loss) from continuing operations was (16.8)%, (58.6)% and (2.9)%, respectively. The Company’s international loss from continuing operations before income taxes and equity income was $40.5 million and $33.1 million for 2024 and 2023, respectively. In 2023, the Company recorded a $14.1 million assets impairment for one of the HE sites in China with no tax benefit. At the same time that the write-off of PPE occurred, the forecast of future taxable income was revised, resulting in decision to record a $3.7 million income tax charge of prior year deferred tax assets in China. In 2024, the Company recorded a $2.1 million net tax benefit from the release of a prior year deferred tax asset in Canada. The Company's total international income tax expense decreased from $26.9 million in 2023 to $22.1 million in 2024 primarily due to the China income tax charge from the assets impairment not recurring in 2024. The Company’s differences in income tax expense for 2024 and 2023 on international earnings and remittances were $29.0 million and $26.4 million, respectively, which included U.S income tax expense on international deemed remittances of $0.3 million and $0.3 million, respectively. The increase is primarily due to the change in mix of income. The Company's U.S. loss from continuing operations before income taxes and equity income was $61.2 million and $19.6 million for 2024 and 2023, respectively. The increase in the loss in 2024 was driven by an increased forward loss provision for the Network Rail contract for Rail, the Rail goodwill impairment, the Rail charge for the remeasurement of long-lived assets, partially offset by increased CE operating performance and the gains from the sale of Reed and Performix. The Company's total U.S. income tax decreased from $4.0 million expense in 2023 to $5.1 million benefit in 2024 primarily due to the increased loss as well as capital loss utilization, partially offset by nondeductible goodwill allocated to the sale of Reed and Performix businesses. The income tax effects of the temporary differences giving rise to the Company's deferred tax assets and liabilities at December 31, 2024 and 2023 are as follows: 2024 (a) 2023 (a) (In thousands) Asset Liability Asset Liability Depreciation and amortization $ — $ 47,816 $ — $ 53,577 Right-of-use assets — 22,851 — 25,417 Operating lease liabilities 23,302 — 25,752 — Expense accruals 26,428 — 33,810 — Inventories 2,324 — 3,779 — Provision for receivables 2,345 — 3,801 — Deferred revenue 11,582 — 6,513 — Operating loss carryforwards 128,412 — 118,309 — Tax credit carryforwards 13,480 — 15,298 — Pensions — 11,916 — 599 Currency adjustments 98 — — 1,171 Section 163(j) disallowed interest expense 40,054 — 25,937 — Research and development 8,236 — 6,013 — Stock based compensation 7,968 — 7,387 — Other 1,881 — — 812 Subtotal 266,110 82,583 246,599 81,576 Valuation allowance (192,745) — (177,888) — Total deferred income taxes $ 73,365 $ 82,583 $ 68,711 $ 81,576 (a) Does not include approximately $1.1 billion of statutory loss carryforwards within Luxembourg for which the Company considers the utilization of these attributes remote and as such no deferred tax asset or corresponding valuation allowance has been recorded. At December 31, 2024, the tax-effected amount of net operating losses ("NOLs") totaled $128.4 million. Tax-effected NOLs from international operations are $116 million. Of that amount, $107.9 million can be carried forward indefinitely and $8.1 million will expire at various times between 2025 and 2044. Tax-effected U.S. state NOLs are $12.4 million. Of that amount, $1.6 million expire at various times between 2025 and 2029, $2.0 million expire at various times between 2030 and 2034, $3.1 million expire at various times between 2035 and 2039 and $5.7 million expire at various times between 2040 and 2044. Valuation allowances of $192.7 million and $177.9 million at December 31, 2024 and 2023, respectively, related principally to deferred tax assets for pension liabilities, NOLs, disallowed interest expense and foreign currency translation that are uncertain as to realizability. In 2024, the Company recorded a $15.0 million valuation allowance increase related to disallowed interest expense, a $14.1 million valuation allowance increase related to current year losses in certain foreign jurisdictions where the Company determined that it is more likely than not that these assets will not be realized, partially offset by a valuation allowance decrease of $7.2 million from the effects of foreign currency translation adjustments and a $5.4 million valuation allowance decrease related to reduced pension liabilities in certain jurisdictions. The Tax Act introduced a transition tax and a territorial tax system, which was effective beginning in 2018. The territorial tax system impacts the Company's overall global capital and legal entity structure, working capital, and repatriation plan on a go-forward basis. The Company asserts that all foreign earnings will be indefinitely reinvested to meet local cash needs. The Company therefore intends to limit distributions to earnings previously taxed in the U.S., or earnings that would qualify for the 100 percent dividends received deduction provided for in the Tax Act, and earnings that would not result in any significant foreign taxes. Therefore, the Company has not recognized a deferred tax liability on its investment in foreign subsidiaries. The Company recognizes accrued interest and penalty expense related to unrecognized income tax benefits in income tax expense or benefit. The Company recognized income tax benefit (expense) of $(0.1) million and $0.4 million during 2024 and 2022, respectively, for interest and penalties. There was no income tax benefit (expense) related to accrued interest and penalties during 2023. The Company has accrued $1.3 million, $1.3 million and $1.3 million for the payment of interest and penalties at December 31, 2024, 2023 and 2022, respectively. A reconciliation of the change in the unrecognized income tax benefits balance from January 1, 2022 to December 31, 2024 is as follows: (In thousands) Unrecognized Deferred Unrecognized Balances, January 1, 2022 $ 3,127 $ (22) $ 3,105 Additions for tax positions related to the current year (includes currency translation adjustment) 189 (1) 188 Statutes of limitation expirations (524) 2 (522) Balance at December 31, 2022 2,792 (21) 2,771 Additions for tax positions related to the current year (includes currency translation adjustment) 439 (1) 438 Statutes of limitation expirations (1,106) 5 (1,101) Balance at December 31, 2023 2,125 (17) 2,108 Additions for tax positions related to the current year (includes currency translation adjustment) 228 9 237 Statutes of limitation expirations (577) — (577) Total unrecognized income tax benefits that, if recognized, would impact the effective income tax rate at December 31, 2024 $ 1,776 $ (8) $ 1,768 Within the next twelve months, it is reasonably possible that up to $0.6 million of unrecognized income tax benefits will be recognized upon settlement of income tax examinations and the expiration of various statutes of limitations. The Company files income tax returns as prescribed by the tax laws of the jurisdictions in which it operates. These tax returns are subject to examinations and possible challenges by the tax authorities. Positions challenged by the tax authorities may be settled or appealed to by the Company. The tax years that remain subject to examination for the Company's major tax jurisdictions as of December 31, 2024 are shown below: Jurisdiction Earliest Open Year Brazil 2020 China 2019 France 2022 United States: Federal income tax 2021 State income tax 2018

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2024
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 ("PRP") for certain byproduct 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 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. The following table summarizes information related to the location and undiscounted amount of the Company's environmental liabilities: (In thousands) December 31 December 31 Current portion of environmental liabilities (a) $ 11,815 $ 7,540 Long-term environmental liabilities 46,585 25,682 Total environmental liabilities (b) $ 58,400 $ 33,222 (a) The current portion of environmental liabilities is included in the caption Other current liabilities on the Consolidated Balance Sheets. (b) The increase in Total environmental liabilities at December 31, 2024 from the prior year is primarily from the salt cakes reserve discussed below regarding the Company's operations in Bahrain. Legal Proceedings In the ordinary course of business, the Company is a defendant or party to various claims and lawsuits, including those discussed below. Unless stated otherwise below, the Company has not determined a loss to be probable or estimable for the legal proceedings. In November 2022, the EPA and the Kentucky Department for Environmental Protection (the “KDEP”) conducted an inspection of Clean Earth of Calvert City LLC’s facility in Calvert City, KY and alleged several violations related to the storage location and volumes of hazardous waste, certain missed inspections and the lack of documentation related to the importing of waste. The Company took corrective actions at the facility, which were completed by February 2023 and the EPA proposed a civil penalty of $0.8 million. On June 30, 2024, the EPA verbally agreed to a settlement involving a combination of civil penalties in the amount of $0.2 million and a Supplemental Environmental Project estimated to cost approximately $1.0 million that requires installing a concrete and storm water management system to enhance compliance and protection of the environment. On January 27, 2020, the EPA issued a Notice of Potential Liability to the Company, along with several other companies, concerning the Newtown Creek Superfund Site located in Kings and Queens Counties in New York, which alleges certain facilities formerly owned or operated by subsidiaries of the Company may have resulted in the discharge of hazardous substances into Newtown Creek or its Dutch Kills tributary. The site has been subject to CERCLA response activities since approximately 2011. The EPA expects to issue a Record of Decision for the sitewide cleanup plan no sooner than 2028 and announced, in July 2021, that it would defer its decision on a potential early action response for the lower two miles of the Creek until the site-wide studies are completed. On August 28, 2024, the EPA released a proposed plan for clean up of the East Branch portion of Newtown Creek. On January 17, 2025, the EPA released its decision approving this early action remedy for the East Branch. The Company is one of 30 PRPs that have received notices, though it is believed other PRPs may exist. The Company vigorously contests the allegations of this notice and currently does not believe that this matter will have a material effect on the Company’s financial position or results from operations. The Company has had ongoing meetings with the SCE over processing salt cakes, a processing byproduct, stored at the Al Hafeerah site. The Company’s Bahrain operations that produced the salt cakes have ceased operations. An Environmental Impact Assessment and Technical Feasibility Study for facilities to process the salt cakes was approved by the SCE during the first quarter of 2018. Commissioning of the facilities was completed during the third quarter of 2021 and the processing of the salt cakes has commenced, with the expectation that the Company would be able to sell the products that resulted from the processing in an amount that would cover the processing costs. During the fourth quarter of 2024, the Company concluded that, despite significant commercial efforts, as well as ongoing discussions with the SCE, it could not sufficiently recover the processing costs from these sales as it had previously estimated. As such, the Company recorded an additional provision of $27.2 million during the quarter. The Company's reserve of $31.9 million as of December 31, 2024 represents the Company’s best estimate of the net costs to fully resolve this matter. The Company will continue to evaluate this reserve and any future change in estimated costs, which could be material to the Company’s results of operations in any single period. On July 27, 2018 Brazil’s Federal and Rio de Janeiro State Public Prosecution Offices (the "MPF" and "MPE", respectively) filed a Civil Public Action against CSN, one of the Company's customers, the Company’s Brazilian subsidiary, the Municipality of Volta Redonda, Brazil, and the Instituto Estadual do Ambiente, the state of Rio de Janeiro's 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 (the "Volta Redonda Court") granted the MPF and MPE an injunction against the defendants 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, the Volta Redonda Court issued two orders fining the Company and CSN for what it viewed as violations of the injunction. The Company appealed the fines and the underlying injunction and, beginning on March 25, 2022, the Volta Redonda Court entered a series of orders suspending the litigation proceedings and staying any additional fines and interest accruals while the parties discuss a possible resolution to the matter. The aggregate amount of fines levied against the Company, exclusive of interest, is approximately 32 million Brazilian reais (or approximately $5 million as of December 31, 2024), plus interest. On October 5, 2024, the Volta Redonda Court determined that, as of August 1, 2024, the Company was not responsible for complying with the injunction because the Company no longer operates at the site. The Company and the other parties continue to discuss a potential resolution related to the portion of the authorities' claims that allegedly occurred prior to August 1, 2024. The Company does not believe that a loss relating to this matter is probable or estimable at this point. In October 2021, the Company received a subpoena and two indictments before the Amsterdam District Court in the Netherlands concerning the Company's operations at a customer site in Ijmuiden, Netherlands. The Amsterdam Public Prosecutor’s Office ("APPO") issued two indictments against the Company, alleging violations in connection with dust releases and/or events alleged to have occurred in 2018 through May 2020 at the site. The action cited provisions which permit fines for the alleged infractions and sought €0.1 million in fines with a smaller amount held in abeyance. On February 2, 2022, the APPO announced that it would further investigate residents’ claims related to this matter. On February 25, 2022, the Amsterdam District Court ruled that the Company was liable for only one alleged violation and that this alleged violation was unintentional. The court issued a fine of €5 thousand, to be held in abeyance . Both the Company and the APPO appealed this ruling. An appellate hearing was held on July 5, 2024, with the APPO seeking €0.3 million in fines. On July 19, 2024, the Court of Appeals ruled that the Company was liable for two alleged intentional violations and issued a fine of €25 thousand. Both the Company and the APPO have appealed this ruling. The Company is vigorously contesting all allegations against it and is also working with its customer to ensure the control of emissions. The Company has contractual indemnity rights from its customer that it believes will substantially cover any fines or penalties. DEA Investigation Prior to the Company’s acquisition of ESOL, Stericycle, Inc. notified the Company that the DEA had served an administrative subpoena on Stericycle, Inc. and executed a search warrant at a facility in Rancho Cordova, CA and an administrative inspection warrant at a facility in Indianapolis, IN. The Company has determined that the DEA and the DTSC have launched investigations involving, at least in part, the ESOL business of collecting, transporting, and destroying controlled substances from retail customers that transferred from Stericycle, Inc. to the Company. The Company is cooperating with these inquiries, which relate primarily to the period before the Company owned the ESOL business. Since the acquisition of the ESOL business, the Company has performed a vigorous review of ESOL’s compliance program related to controlled substances and has made material changes to the manner in which controlled substances are transported from retail customers to DEA-registered facilities for destruction. Pursuant to an agreement with Stericycle, the Company has contractual recourse for any material loss the Company has determined is reasonably possible. The Company has not accrued any amounts in respect of these investigations and does not believe a loss is possible. Brazilian Tax Disputes On December 30, 2020, the Company received an assessment from the municipal tax authority in Ipatinga, Brazil alleging $1.7 million in unpaid service taxes from the period 2015 to 2020. This dispute is currently in the collection action phase of the legal process and the amount assessed include interest charges may increase at statutorily determined amounts per month and are assessed on the aggregate amount of the principal and penalties. In addition, at the collection action, the losing party 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. After calculating the interest and penalties accrued, the Company estimates that the current overall potential liability for this case is approximately $5.6 million at December 31, 2024. On July 21, 2023, the Company filed the last administrative appeal against the decision that maintained the assessment and a final administrative decision is still pending. Due to the multiple defenses that are available, the Company does not believe a loss is probable. The Company intends to continue its practice of vigorously defending itself against this tax claim under various alternatives, including judicial appeal. The Company will continue to evaluate its potential liability with regard to this claim on a quarterly basis; however, it is not possible to predict the ultimate outcome of the tax-related dispute in Brazil. No loss provision has been recorded in the Company's Consolidated Financial Statements for the dispute 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 this tax dispute would have a material adverse effect on the Company's financial condition, results of operations or cash flows. Asbestos Actions The Company is named as one of many defendants 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. As of December 2024, there were approximately 17,000 pending asbestos personal injury actions filed against the Company. The vast majority of these actions were filed in the New York Supreme Court (New York County), of which the majority of such actions were on the Deferred/Inactive Docket created by the New York Supreme 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. A relatively small portion of cases are on the Active or In Extremis docket in New York County or on active dockets in other jurisdictions. The complaints in most of those actions generally follow a form that contains a standard demand of significant damages, regardless of the individual plaintiff's alleged medical condition, and without identifying any Company product. The Company will continue to vigorously defend against such claims and is confident that it will be successful in doing so. 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. 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. As of December 2024, the Company has successfully dismissed approximately 28,500 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 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. Other On November 5, 2020, a worker suffered a fatal injury at a site owned by the Company’s customer, Gerdau Ameristeel US, Inc. ("Gerdau"), in Midlothian, TX. Although the Company was not directly involved in the accident, the worker was employed by a sub-contractor of a sub-contractor of the Company. On May 11, 2023, the parties completed a formal settlement agreement, settling the claims brought by the worker's family. The Company paid its insurance deductible of $5.0 million and recorded an indemnification receivable from Gerdau for the recovery of certain losses based upon the contractual indemnity rights. On August 25, 2023, the Company initiated arbitration proceedings against Gerdau before the American Arbitration Association to enforce its contractual indemnity rights. On December 18, 2024, the Company and Gerdau entered into a settlement agreement to resolve the Company's claims against Gerdau which settled the full indemnification receivable balance. 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 has been determined to be 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 Consolidated Balance Sheets. See Note 1, Summary of Significant Accounting Policies for additional information on Accrued insurance and loss reserves.

Capital Stock

Capital Stock	12 Months Ended
	Dec. 31, 2024
Equity [Abstract]
Capital Stock	Capital Stock The authorized capital stock of the Company consists of 150,000,000 shares of common stock and 4,000,000 shares of preferred stock, both having a par value of $1.25 per share. The preferred stock is issuable in series with terms as fixed by the Board. No preferred stock has been issued. The following table summarizes the Company's common stock activity for each period during the twelve months ended 2022, 2023 and 2024: Shares Treasury Shares Outstanding As of January 1, 2022 115,906,393 36,690,847 79,215,546 Shares issued for vested restricted stock units 341,051 131,089 209,962 Shares issued for vested restricted stock awards 87,765 40,304 47,461 Stock appreciation rights exercised 23,311 6,640 16,671 As of December 31, 2022 116,358,520 36,868,880 79,489,640 Shares issued for vested restricted stock units 401,385 122,659 278,726 Shares issued for vested restricted stock awards 124,106 57,637 66,469 As of December 31, 2023 116,884,011 37,049,176 79,834,835 Shares issued for vested restricted stock units 590,133 227,794 362,339 Stock appreciation rights exercised 844 241 603 As of December 31, 2024 117,474,988 37,277,211 80,197,777 The following is a reconciliation of the average shares of common stock used to compute basic earnings per common share to the shares used to compute diluted earnings per common share as shown on the Consolidated Statements of Operations: (In thousands, except per share data) 2024 2023 2022 Income (loss) from continuing operations attributable to Enviri Corporation common stockholders $ (124,058) $ (82,320) $ (176,569) Weighted-average shares outstanding—basic 80,118 79,796 79,493 Dilutive effect of stock-based compensation — — — Weighted-average shares outstanding—diluted 80,118 79,796 79,493 Income (loss) from continuing operations per common share, attributable to Enviri Corporation common stockholders: Basic $ (1.55) $ (1.03) $ (2.22) Diluted $ (1.55) $ (1.03) $ (2.22) The following average outstanding stock-based compensation units were not included in the computation of diluted earnings per share because the effect was antidilutive or the market conditions for the performance share units were not met: (In thousands) 2024 2023 2022 Restricted stock units 1,476 1,219 672 Stock appreciation rights 2,618 2,303 2,092 Performance share units 1,797 1,341 1,040

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2024
Share-Based Payment Arrangement [Abstract]
Stock-Based Compensation	Stock-Based Compensation The 2013 Equity and Incentive Plan as amended (the "2013 Plan") authorizes the i ssuance of up to 13.7 million shares of the Company's common stock for use in paying incentive compensation awards in the form of stock options or other equity awards such as restricted stock, restricted stock units ("RSUs"), stock appreciation rights ("SARs") or performance share units ("PSUs"). Of the 13.7 million shares authorized, a maximum of 9.7 million shares may be issued for awards other than option rights or SARs, as defined in the 2013 Plan. The 2016 Non-Employee Directors' Long-Term Equity Compensation Plan, as amended (the "2016 Plan"), authorizes the issuance of up to 800 thousand shares of the Company's common stock for equity awards. Both plans have been approved by the Company's stockholders. At December 31, 2024, there were 3.2 million shares available for granting equity awards under the 2013 Plan, of which 2.3 million shares were available for awards other than option rights or SARs. At December 31, 2024, there were 101 thousand shares available for granting equity awards under the 2016 Plan. Restricted Stock Units The Board approves the granting of performance-based RSUs as the long-term equity component of director, officer and certain key employee compensation. The RSUs require no payment from the recipient and compensation cost is measured based on the market price of the Company's common stock on the grant date and is generally recorded over the vesting period. RSUs granted to officers and certain key employees in 2022 , 2023 and 2024 either vest on a pro-rata basis over three years or upon obtainment of specified retirement or years of service criteria. The vesting period for RSUs granted to non-employee directors is one year and each RSU is exchanged for an equal number of shares of the Company's common stock upon vesting for awards issued under the 2016 and 2013 Plans. There is no option for cash payment. The following table summarizes RSUs issued and the compensation expense recorded for the years ended December 31, 2024, 2023, and 2022: RSUs (a) Weighted Average Fair Value Expense (Dollars in thousands, except per unit) 2024 2023 2022 Directors: 2021 23,224 21.53 — — 167 2022 63,696 7.85 — 167 333 2023 80,705 9.03 213 516 — 2024 80,125 7.80 406 — — Employees: 2019 270,864 22.25 — — 320 2020 522,087 8.22 — 90 800 2021 343,125 18.62 157 946 1,355 2022 450,915 12.36 1,035 1,095 1,547 2023 926,010 7.09 1,962 1,722 — 2024 825,499 8.22 2,565 — — Total $ 6,338 $ 4,536 $ 4,522 (a) Represents number of awards originally issued. RSU activity for the year ended December 31, 2024 was as follows: Number of Shares Weighted Average Non-vested at December 31, 2023 1,219,321 $ 8.63 Granted 905,624 8.19 Vested (591,442) 9.46 Forfeited (57,847) 8.55 Non-vested at December 31, 2024 1,475,656 $ 8.01 At December 31, 2024, the total unrecognized compensation expense related to non-vested RSUs was $6.8 million, which will be recognized over a weighted-average period of 1.8 years. The total fair value of RSU's vested in 2024, 2023 and 2022 was $5.6 million, $4.1 million and $5.1 million, respectively. Stock Appreciation Rights The Board approves the granting of SARs to officers and certain key employees under the 2013 Plan. The SARs generally vest on a pro-rata three-year basis from the grant date or upon specified retirement or years of service criteria and expire no later than ten years after the grant date. The exercise price of the SARs is equal to the fair value of Enviri common stock on the grant date. Upon exercise, shares of the Company's common stock are issued based on the increase in the fair value of the Company's common stock over the exercise price of the SAR. SARs do not have an option for cash payment. The table below summarizes the total SARs granted and the fair value of each grant estimated on the grant date using a Black-Scholes pricing model with the following assumptions: Number of Shares Granted Risk-free Interest Rate Dividend Yield Expected Life (Years) Volatility SAR Grant Price Fair Value of SAR March 2022 Grant 312,987 1.67 % — % 6.0 60.3 % $ 12.65 $ 7.20 September 2022 Grant 10,000 3.56 % — % 6.0 60.6 % $ 5.02 $ 2.97 October 2022 Grant 10,000 4.10 % — % 6.0 61.3 % $ 5.26 $ 3.17 December 2022 Grant 10,000 3.75 % — % 6.0 62.4 % $ 6.15 $ 3.72 March 2023 Grant 404,594 4.20 % — % 6.0 62.6 % $ 7.45 $ 4.56 May 2023 Grant 48,427 3.48 % — % 6.0 63.0 % $ 9.31 $ 5.64 March 2024 Grant 567,967 4.04 % — % 6.0 63.4 % $ 8.20 $ 5.04 SARs activity for the year ended December 31, 2024 was as follows: Number of Shares Weighted Average Exercise Price Aggregate Intrinsic Value (in millions) (b) Outstanding, December 31, 2023 2,303,018 $ 13.01 $ 1.30 Granted 567,967 8.20 Exercised (6,563) 7.45 Forfeited/Expired (246,204) 21.31 Outstanding, December 31, 2024 2,618,218 $ 11.20 $ 0.40 (b) Intrinsic value is defined as the difference between the current market value and the exercise price, for those SARs where the market price exceeds the exercise price. There was no intrinsic value for SARs exercised in 2024 and 2022. The were no SARs exercised in 2023. The following table summarizes information related to outstanding and exercisable SARs at December 31, 2024: SARs Outstanding SARs Exercisable Range of Exercisable Prices Vested Non-vested Weighted-Average Exercise Price per Share Weighted-Average Remaining Contractual Life in Years Number Exercisable Weighted-Average Exercise Price per Share $5.02 - $13.70 1,103,357 928,964 $ 9.07 6.30 1,103,357 $ 9.69 $16.53 - $22.51 585,897 — 18.58 2.65 585,897 18.58 1,689,254 928,964 $ 11.20 5.48 1,689,254 $ 12.77 Total compensation expense related to SARs was $2.1 million, $1.5 million and $1.5 million for the years ended December 31, 2024, 2023 and 2022, respectively. At December 31, 2024, total unrecognized compensation expense related to non-vested SARs was $2.8 million, which will be recognized over a weighted average period of 1.3 years. Weighted-average grant date fair value of non-vested SARs for the year ended December 31, 2024 was as follows: Number of Shares Weighted-Average Grant Date Fair Value Non-vested shares, December 31, 2023 598,304 $ 5.51 Granted 567,967 8.20 Vested (220,327) 6.17 Forfeited (16,980) 5.16 Non-vested shares, December 31, 2024 928,964 $ 5.07 Performance Share Units The Board approves the granting of PSUs to officers and certain key employees that may be earned based on the Company's total shareholder return over the three-year performance period. PSUs are paid out at the end of each performance period based on the Company’s performance, which is measured by determining the percentile rank of the total shareholder return of the Company's common stock in relation to the total shareholder return of a specific peer group of companies. The peer group of companies utilized is the S&P Smallcap 600 Industrials Index. The payment of PSUs following the performance period will be based in accordance with the scale set forth in the PSU agreements, and may range from 0% to 200% of the initial grant. PSUs do not have an option for cash payment. Under the 2013 Plan, the Company granted the following shares presented in the table below and estimated the fair value of these grants on the grant date using a Monte Carlo pricing model with the following assumptions: PSUs Issued Number of Shares Granted Risk-free Interest rate Dividend Yield Expected Life (Years) Volatility Fair Value per PSU March 2022 Grant 500,624 1.59 % — % 2.83 50.4 % $ 16.54 March 2023 Grant 758,965 4.67 % — % 2.82 43.9 % $ 10.91 May 2023 Grant 29,337 3.75 % — % 2.65 41.5 % $ 15.24 March 2024 Grant 778,702 4.26 % — % 2.81 39.8 % $ 12.04 Total compensation expense related to PSUs was $8.3 million, $5.9 million and $4.3 million for the years ended December 31, 2024, 2023 and 2022, respectively. At December 31, 2024, total unrecognized compensation expense related to non-vested PSUs was $7.3 million, which will be recognized over a weighted average period of 1.7 years. A summary of the Company's non-vested PSU activity during the year ending December 31, 2024 was as follows: Number of Shares Weighted-Average Grant Date Fair Value Non-vested shares, December 31, 2023 1,108,256 $ 12.87 Granted 767,699 12.04 Vested, not issued (a) (339,496) 16.54 Forfeited (79,071) 12.80 Non-vested shares, December 31, 2024 1,457,388 $ 11.58 (a) The measurement period for PSUs issued in 2022 ended on December 31, 2024 and these shares vested but will not be issued until the Board certifies the measurement period results in early 2025. A total of 0 shares are expected to be issued. Other Stock Grants In connection with the Company's appointment of its interim Senior Vice President and Chief Financial Officer ("ICFO") in August 2022, a monthly common stock grant equal to $0.1 million determined at the closing price of the Company's common stock on the last trading day of each month was issued as part of the ICFO's compensation through the end of his service date in October 2023. During the years ended December 31, 2023 and 2022, the Company issued 124,106 and 87,765 shares, respectively recorded and compensation expense of $0.9 million and $0.5 million, respectively.

Financial Instruments

Financial Instruments	12 Months Ended
	Dec. 31, 2024
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Financial Instruments	Financial Instruments Off-Balance Sheet Risk As collateral for the Company's performance and to insurers, the Company is contingently liable under standby letters of credit, bonds, bank guarantees and performance guarantees in the amounts of $451.8 million, $489.6 million and $500.4 million at December 31, 2024, 2023 and 2022, respectively. The expiration periods of the standby letters of credit, bonds and bank guarantees range from less than one year to approximately 10 years, but the majority are generally in force for approximately two years. Certain issues have no scheduled expiration date. The Company pays fees to various banks and insurance companies that typically range from approximately 0.2% to 3.0% per annum of the instrument's face value. If the Company were required to obtain replacement standby letters of credit, bonds and bank guarantees at December 31, 2024 for those currently outstanding, it is the Company's opinion that the replacement costs would be within the present fee structure. The Company has currency exposures in approximately 30 countries. The Company's primary foreign currency exposures during 2024 were in the European Union, the U.K., Brazil and China, as well as in Egypt, Turkey and Argentina. Off-Balance Sheet Risk—Third-Party Guarantees Any liabilities related to the Company's obligation to stand ready to act on third-party guarantees are included in Other current liabilities or Other liabilities (as appropriate) on the Company's Consolidated Balance Sheets. Any recognition of these liabilities did not have a material impact on the Company's financial position or results of operations for 2024, 2023 or 2022. In the normal course of business, legal indemnifications are provided related primarily to the performance of the Company's products and services and patent and trademark infringement of the products and services sold. These indemnifications generally relate to the performance (regarding function, not price) of the respective products or services and, therefore, no liability is recognized related to the fair value of such guarantees. Derivative Instruments and Hedging Activities The Company uses derivative instruments, including foreign currency exchange forward contracts and interest rate swaps, 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 Company's Consolidated Balance Sheets at fair value. The accounting for changes in the fair value of derivatives depends on the intended use of the derivative, whether the Company has elected to designate a derivative in a hedging relationship and apply hedge accounting and whether the hedging relationship has satisfied the criteria necessary to apply hedge accounting. Derivatives designated and qualifying as a hedge of the exposure to variability in expected future cash flows, or other types of forecasted transactions, are considered cash flow hedges. Hedge accounting generally provides for the matching of the timing of gain or loss recognition on the hedging instrument with the recognition of the earnings effect of the hedged forecasted transactions in a cash flow hedge. The Company may enter into derivative contracts that are intended to economically hedge certain of its risks, even though hedge accounting does not apply, or the Company elects not to apply hedge accounting. 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 and interest rate swaps 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. 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 fair value of outstanding derivative contracts recorded as assets and liabilities on the Company's 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 December 31, 2024 Asset derivatives (Level 2): Foreign currency exchange forward contracts Other current assets $ 347 $ 7,590 $ 7,937 Interest rate swaps Other assets 5,250 — 5,250 Total $ 5,597 $ 7,590 $ 13,187 Liability derivatives (Level 2): Foreign currency exchange forward contracts Other current liabilities $ 80 $ 987 $ 1,067 Interest rate swaps Other current liabilities 217 — 217 Total $ 297 $ 987 $ 1,284 December 31, 2023 Asset derivatives (Level 2): Foreign currency exchange forward contracts Other current assets $ 77 $ 1,597 $ 1,674 Interest rate swaps Other current assets 1,443 — 1,443 Total $ 1,520 $ 1,597 $ 3,117 Liability derivatives (Level 2): Foreign currency exchange forward contracts Other current liabilities $ 561 $ 8,064 $ 8,625 Interest rate swaps Other liabilities 2,150 — 2,150 Total $ 2,711 $ 8,064 $ 10,775 All of the Company's derivatives are recorded on the Consolidated Balance Sheets at gross amounts and not offset. All of the Company's interest rate swaps and certain foreign currency exchange forward contracts are transacted under 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 are subject to enforceable master netting arrangements which, if offset, would have resulted in a $2.2 million net asset at December 31, 2024 and a $0.5 million net liability at December 31, 2023. The effect of derivative instruments on the Company's Consolidated Statements of Operations and the Consolidated Statements of Comprehensive Income (Loss) was as follows: Derivatives Designated as Hedging Instruments Gain (Loss) Recognized in OCI on Derivatives Loss (Gain) Reclassified from AOCI into Income - Effective Portion or Equity (In thousands) 2024 2023 2022 2024 2023 2022 Foreign currency exchange forward contracts $ 592 $ (1,696) $ 1,966 $ (695) $ 1,638 $ (1,746) Interest rate swaps 8,757 1,869 — (3,018) (2,576) 4,245 $ 9,349 $ 173 $ 1,966 $ (3,713) $ (938) $ 2,499 The locations and amounts of gain (loss) recognized on the Consolidated Statements of Operations are as follows: 2024 (in thousands) Product Revenues Interest Expense Total amounts in the Consolidated Statements of Operations in which the effects of cash flow hedges are recorded $ 372,452 $ (112,217) Interest rate swaps: Gain or (loss) reclassified from AOCI into income — 3,018 Foreign exchange contracts: Gain or (loss) reclassified from AOCI into income 695 — 2023 (in thousands) Product Revenues Interest Expense Total amounts in the Consolidated Statements of Operations in which the effects of cash flow hedges are recorded $ 434,308 $ (107,081) Interest rate swaps: Gain or (loss) reclassified from AOCI into income — 2,576 Foreign exchange contracts: Gain or (loss) reclassified from AOCI into income (1,638) — 2022 Product Revenues Interest Expense Total amounts in the Consolidated Statements of Operations in which the effects of cash flow hedges are recorded $ 376,398 $ (76,807) Interest rate swaps: Gain or (loss) reclassified from AOCI into income — (4,245) Amount recognized in earnings due to ineffectiveness — 1,862 Foreign exchange contracts: Gain or (loss) reclassified from AOCI into income 1,746 — Derivatives Not Designated as Hedging Instruments Location of Gain (Loss) Recognized in Income on Derivatives Amount of Gain (Loss) Recognized in Income on Derivatives for the Twelve Months Ended December 31 (a) (In thousands) 2024 2023 2022 Foreign currency exchange forward contracts Cost of services and products sold $ 25,184 $ 426 $ 19,808 (a) These gains (losses) offset amounts recognized in cost of sales 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 monthly exchange rates during the respective periods. The Company uses derivative instruments to hedge cash flows related to foreign currency fluctuations. The outstanding foreign currency exchange forward contracts 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 AOCI, 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 sales principally as a result of intercompany or third-party foreign currency exposures. At December 31, 2024 and December 31, 2023, the notional amounts of foreign currency exchange forward contracts were $593.7 million and $633.3 million, respectively. These contracts primarily hedge British pounds sterling and Euros against other currencies and mature through August 2027. 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 gain (loss) of $2.4 million, $1.1 million and $2.6 million during 2024, 2023 and 2022, respectively, related to hedges of net investments in OCI. Interest Rate Swaps The Company uses interest rate swaps in conjunction with certain variable rate 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 OCI. In the first quarter of 2023, the Company entered into a series of interest rate swaps with a scheduled maturity of December 2025. The swaps have the effect of converting $300.0 million of the Term Loan from a floating interest rate to a fixed interest rate and are classified as cash flow hedges. The fixed rates provided by these swaps, ranging from 4.16% to 4.21%, replace the adjusted SOFR rate in the interest calculation. In October 2024, the Company entered into a new series of interest rate swaps that will be in effect upon the maturity of the existing interest rate swaps in December 2025 and will mature in March 2028. These forward swaps will continue to have the same effect of converting $300.0 million from the Term Loan from a floating interest rate to a fixed interest rate and will be classified as cash flow hedges. These swaps will provide fixed interest rates that range from 3.06% to 3.12% and will continue to replace the adjusted SOFR rate in the interest calculation. 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 December 31, 2024 and 2023, the total fair value of long-term debt, including current maturities, was $1,419.7 million and $1,394.5 million, respectively, compared with a carrying value of $1,444.4 million and $1,429.0 million, respectively. Fair values for debt are based upon pricing models using market-based inputs (Level 2) for similar issues or on the current rates offered to the Company for debt of the same remaining maturities. Concentrations of Credit Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist principally of cash and cash equivalents and accounts receivables. The Company places cash and cash equivalents with high-quality financial institutions and, by policy, limits the amount of credit exposure to any single institution. Concentrations of credit risk with respect to accounts receivable exist in HE, which have several large customers throughout the world with significant accounts receivable balances. Consolidation in the global steel industry could result in an increase in concentration of credit risk for the Company. CE also has significant sales to several U.S. customers. The Company generally does not require collateral or other security to support customer receivables. If a receivable from one or more of the Company's larger customers becomes uncollectible, it could have a material effect on the Company's results of operations or cash flows.

Information by Segment and Geog

Information by Segment and Geographic Area	12 Months Ended
	Dec. 31, 2024
Segment Reporting [Abstract]
Information by Segment and Geographic Area	Information by Segment and Geographic Area The Company reports information about operating segments using the "management approach," which is based on the way management organizes and reports the segments within the enterprise for making operating decisions and assessing performance. The Company's reportable segments are identified based upon differences in products, services and markets served. In 2024, the Company had three reportable segments. These segments and the types of products and services offered include the following: Harsco Environmental HE is a global provider of on-site environmental services for the management of waste and byproduct streams from our customers, which includes resource recovery and recycling of waste materials, materials handling and logistical support and aluminum dross and scrap management. HE also manufactures value-added downstream products from industrial waste streams, or ecoproducts, which includes road surfacing materials, metallurgical additives, agriculture and turf products and cement additives. Clean Earth CE provides specialty waste processing solutions for customers in the industrial, retail, healthcare and construction industries in the U.S. CE's services include the treatment, recycling and beneficial reuse of hazardous and non-hazardous wastes and the processing of contaminated soil and dredged materials. Harsco Rail Rail is a global provider of railway track maintenance equipment and services. Rail's products include highly engineered railway track maintenance equipment, after-market parts and safety and diagnostics technology systems. In addition, Rail provides railway maintenance services to major railways, mass transit systems and equipment leasing companies. Information by Geographical Areas Countries with revenues from unaffiliated customers or net PP&E of 10% or more of the consolidated totals for at least one of the periods presented below are as follows: Revenues from Unaffiliated Customers Years ended December 31 (In thousands) 2024 2023 2022 By geographic location (a) : U.S. $ 1,340,795 $ 1,406,262 $ 1,239,345 International 1,001,850 959,758 894,636 Total revenues from unaffiliated customers $ 2,342,645 $ 2,366,020 $ 2,133,981 (a) Revenues are attributed to individual countries based on the location of the facility generating the revenue. Property, Plant and Equipment, Net December 31 (In thousands) 2024 2023 By geographic location: U.S. $ 338,679 $ 339,231 International 325,613 368,166 Total property, plant and equipment, net $ 664,292 $ 707,397 No customer provided in excess of 10% of the Company's consolidated revenues in 2024, 2023 and 2022. In 2024, 2023 and 2022, HE had one customer that provided in excess of 10% of its revenues under multiple long-term contracts at several mill sites. Should additional consolidations occur involving some of the steel industry's larger companies which are customers of the Company, it would result in an increase in concentration of credit risk for the Company. The loss of any one of the contracts would not have a material adverse effect upon the Company's financial position or cash flows; however, it could have a significant effect on quarterly or annual results of operations. In 2024, 2023, and 2022, CE had one customer that provided in excess of 10% of its revenue. The loss of this customer would not have a material adverse impact on the Company's financial positions or cash flows; however, it could have a material effect on quarterly or annual results of operations. In 2024 and 2022, Rail had two customers that provided more than 10% of the segment total revenues and, in 2023, Rail had one customer that provided more than 10% of the segment total revenues. The loss of either customer would not have a material adverse impact on the Company's financial positions or cash flows; however, it could have a material effect on quarterly or annual results of operations. Operating Information by Segment The accounting policies for the three reportable segments are consistently applied, as described in Note 1, Summary of Significant Accounting Policies. The Company's chief operating decision maker (the "CODM") is the Company's Chairman and Chief Executive Officer. The CODM uses segment operating income/(loss) as the profit measure to evaluate segment performance and allocate resources across segments. Corporate unallocated expenses, interest income, interest expense, facility fees and debt-related income (expense) and defined benefit pension income (expense) are centrally managed costs and are, therefore, excluded from this profit measure to provide better understanding of the Company's segment operating results. The CODM considers variances of actual performance to the Company's annual operating plan and periodic forecasts when making decisions. The following tables include information about the Company's revenues and operating income (loss) by reporting segment, along with significant segment expenses and other segment information, for the years ended December 31, 2024, 2023 and 2022: Year Ended December 31, 2024 (in thousands) Harsco Clean Earth Harsco Rail Total Segment Corporate Total Segment Profit and Loss: Total revenues 1,111,512 939,845 291,288 $ 2,342,645 — $ 2,342,645 Less: Cost of services and products sold (a) 948,591 690,160 270,330 1,909,081 — 1,909,081 Selling, general and administrative expenses 113,845 156,378 48,461 318,684 40,704 359,388 Goodwill and other intangible asset impairment charges 2,840 — 13,026 15,866 — 15,866 Property, plant and equipment impairment charge 23,444 — — 23,444 — 23,444 Remeasurement of long-lived assets — — 10,695 10,695 — 10,695 Gain on sale of businesses, net (10,029) — — (10,029) (449) (10,478) Other segment activities (a)(b) 808 1,151 6,808 8,767 (5,863) 2,904 Operating income (loss) from continuing operations 32,013 92,156 (58,032) $ 66,137 (34,392) $ 31,745 Plus: Interest income 6,795 Interest expense (112,217) Facility fees and debt-related income (expense) (11,265) Defined benefit pension income (expense) (16,728) Income (loss) from continuing operations before income taxes and equity income $ (101,670) Other Segment Information: Depreciation 109,756 33,840 3,478 $ 147,074 1,255 $ 148,329 Amortization (c) 3,068 23,976 224 $ 27,268 4,203 $ 31,471 Capital expenditures 98,845 32,754 4,756 $ 136,355 236 $ 136,591 Total assets 1,263,031 993,598 350,157 $ 2,606,786 43,447 $ 2,650,233 Year Ended December 31, 2023 (in thousands) Harsco Clean Harsco Total Segment Corporate Total Segment Profit and Loss: Total revenues 1,140,904 928,321 296,795 $ 2,366,020 — $ 2,366,020 Less: Cost of services and products sold (a) 942,219 694,756 277,812 1,914,787 — 1,914,787 Selling, general and administrative expenses 109,131 154,513 45,770 309,414 44,571 353,985 Property, plant and equipment impairment charge 14,099 — — 14,099 — 14,099 Other segment activities (a)(b) (2,180) 2,078 4,884 4,782 (1,571) 3,211 Operating income (loss) from continuing operations 77,635 76,974 (31,671) $ 122,938 (43,000) $ 79,938 Plus: Interest income 6,809 Interest expense (107,081) Facility fees and debt-related income (expense) (10,762) Defined benefit pension income (expense) (21,574) Income (loss) from continuing operations before income taxes and equity income $ (52,670) Other Segment Information: Depreciation 113,571 23,252 — $ 136,823 2,133 $ 138,956 Amortization (c) 4,030 24,583 — $ 28,613 3,795 $ 32,408 Capital expenditures 104,045 32,100 2,453 $ 138,598 427 $ 139,025 Total assets 1,417,278 981,723 369,022 $ 2,768,023 86,675 $ 2,854,698 Year Ended December 31, 2022 (in thousands) Harsco Clean Harsco Total Segment Corporate Total Segment Profit and Loss: Total revenues 1,061,239 827,826 244,916 $ 2,133,981 — $ 2,133,981 Less: Cost of services and products sold (a) 881,249 675,283 242,951 1,799,483 — 1,799,483 Selling, general and administrative expenses 99,855 129,401 40,967 270,223 34,642 304,865 Goodwill and other intangible asset impairment charges 15,000 104,580 — 119,580 — 119,580 Other segment activities (a)(b) 5,576 347 4,679 10,602 347 10,949 Operating income (loss) from continuing operations 59,559 (81,785) (43,681) $ (65,907) (34,989) $ (100,896) Plus: Interest income 3,829 Interest expense (76,807) Facility fees and debt-related income (expense) (2,956) Defined benefit pension income (expense) 8,933 Income (loss) from continuing operations before income taxes and equity income $ (167,897) Other Segment Information: Depreciation 108,880 18,836 — $ 127,716 1,996 $ 129,712 Amortization (c) 6,809 24,299 — $ 31,108 3,029 $ 34,137 Capital expenditures 109,508 21,996 1,618 $ 133,122 4,038 $ 137,160 (a) Cost of services and products sold is a significant expense category provided to the CODM at the segment-level. (b) Other segment activities include amounts reflected in the captions, Research and development costs, Cost of services and products sold and Other (income) expenses, net, on the Company's Consolidated Statements of Operations.

Revenue Recognition

Revenue Recognition	12 Months Ended
	Dec. 31, 2024
Revenue from Contract with Customer [Abstract]
Revenue Recognition	Revenues 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 CE and the service components of HE and Rail. Product revenues include portions of HE and Rail. A summary of the Company's revenues by primary geographical markets as well as by key product and service groups for the years ended December 31, 2024, 2023 and 2022 is as follows: Year Ended December 31, 2024 (In thousands) Harsco Clean Earth Segment Harsco Rail Segment Consolidated Totals Primary Geographical Markets (a) : North America $ 292,274 $ 939,845 $ 173,424 $ 1,405,543 Western Europe 425,775 — 84,398 510,173 Latin America (b) 154,684 — 5,578 160,262 Asia-Pacific 117,523 — 27,888 145,411 Middle East and Africa 103,957 — — 103,957 Eastern Europe 17,299 — — 17,299 Total Revenues $ 1,111,512 $ 939,845 $ 291,288 $ 2,342,645 Key Product and Service Groups: Environmental services related to resource recovery for metals manufacturing; and related logistical services $ 967,188 $ — $ — $ 967,188 Ecoproducts 120,896 — — 120,896 Environmental systems for aluminum dross and scrap processing 23,428 — — 23,428 Railway track maintenance equipment — — 113,039 113,039 After market parts and services; safety and diagnostic technology — — 117,327 117,327 Railway contracting services — — 60,922 60,922 Hazardous waste processing solutions — 778,402 — 778,402 Soil and dredged materials processing and reuse solutions — 161,443 — 161,443 Total Revenues $ 1,111,512 $ 939,845 $ 291,288 $ 2,342,645 Year Ended December 31, 2023 (In thousands) Harsco Environmental Segment Clean Earth Segment Harsco Rail Segment Consolidated Totals Primary Geographical Markets (a) : North America $ 318,574 $ 928,321 $ 214,893 $ 1,461,788 Western Europe 431,893 — 57,301 489,194 Latin America (b) 170,194 — 2,540 172,734 Asia-Pacific 113,800 — 22,061 135,861 Middle East and Africa 86,867 — — 86,867 Eastern Europe 19,576 — — 19,576 Total Revenues $ 1,140,904 $ 928,321 $ 296,795 $ 2,366,020 Key Product and Service Groups: Environmental services related to resource recovery for metals manufacturing; and related logistical services $ 950,961 $ — $ — $ 950,961 Ecoproducts 162,291 — — 162,291 Environmental systems for aluminum dross and scrap processing 27,652 — — 27,652 Railway track maintenance equipment — — 128,155 128,155 After market parts and services; safety and diagnostic technology — — 121,039 121,039 Railway contracting services — — 47,601 47,601 Hazardous waste processing solutions — 767,338 — 767,338 Soil and dredged materials processing and reuse solutions — 160,983 — 160,983 Total Revenues $ 1,140,904 $ 928,321 $ 296,795 $ 2,366,020 Year Ended December 31, 2022 (In thousands) Harsco Environmental Segment Clean Earth Segment Harsco Rail Segment Consolidated Totals Primary Geographical Markets (a) : North America $ 297,544 $ 827,826 $ 163,998 $ 1,289,368 Western Europe 389,713 — 45,507 435,220 Latin America (b) 155,235 — 1,556 156,791 Asia-Pacific 119,433 — 33,855 153,288 Middle East and Africa 79,562 — — 79,562 Eastern Europe 19,752 — — 19,752 Total Revenues $ 1,061,239 $ 827,826 $ 244,916 $ 2,133,981 Key Product and Service Groups: Environmental services related to resource recovery for metals manufacturing; and related logistical services $ 900,426 $ — $ — $ 900,426 Ecoproducts 145,911 — — 145,911 Environmental systems for aluminum dross and scrap processing 14,902 — — 14,902 Railway track maintenance equipment — — 100,032 100,032 After market parts and services; safety and diagnostic technology — — 118,829 118,829 Railway contracting services — — 26,055 26,055 Hazardous waste processing solutions — 681,804 — 681,804 Soil and dredged materials processing and reuse solutions — 146,022 — 146,022 Total Revenues $ 1,061,239 $ 827,826 $ 244,916 $ 2,133,981 (a) Revenues are attributed to individual countries based on the location of the facility generating the revenue. (b) Includes Mexico. The Company may receive payments in advance of earning revenue (advances on contracts), which are included in Other current liabilities and Other liabilities on the Consolidated Balance Sheets. The Company may recognize revenue in advance of being able to contractually invoice the customer (contract assets), which is included in Other current assets on the Consolidated Balance Sheets. Contract assets are transferred to Trade accounts receivable, net, when the right to payment becomes unconditional. Contract assets and advances on contracts are reported as a net position, on a contract-by-contract basis, at the end of each reporting period. The Company had contract assets totaling $97.2 million and $86.9 million at December 31, 2024 and 2023, respectively. The increase is due principally to additional contract assets recognized in excess of the transfer of contract assets to accounts receivable. The Company had advances on contracts totaling $23.9 million and $38.6 million at December 31, 2024 and 2023, respectively. The decrease is due principally to recognition of revenue on previously received advances on contracts in excess of receipts of new advances on contracts during the period. During the year ended December 31, 2024, the Company recognized approximately $32.7 million of revenue related to amounts previously included in advances on contracts. The table below represents the expected fulfillment year of Company's fixed, unsatisfied performance obligations, where the expected contract duration exceeds one year, by segment, and exclude any variable fees, fixed fees subject to indexation and any performance obligations expected to be satisfied within one year: (In thousands) Harsco Harsco Rail Segment 2025 $ 17,019 $ 51,037 2026 15,367 24,980 2027 12,803 17,955 2028 11,121 5,137 2029 3,132 4,038 Thereafter 3,132 2,676 Total remaining performance obligations $ 62,574 $ 105,823 Rail is currently manufacturing highly-engineered equipment under large long-term fixed-price contracts with Network Rail, Deutsche Bahn, and SBB. The Company has previously recognized estimated forward loss provisions related to these contracts of $32.8 million and $44.5 million for the years ended 2023 and 2022 related to these contracts due to several factors, such as material and labor cost inflation, supply chain delays, the bankruptcy of a key vendor and increased engineering efforts. These challenges carried into 2024 and the Company recorded an additional $32.7 million forward loss provision for these contracts for the year ended December 31, 2024, as discussed further below. For the Network Rail contract, the Company recorded additional loss provisions of $16.1 million in 2024, with $2.8 million recorded in the fourth quarter. This additional loss is primarily related to increased estimated liquidated damages due to delays in the estimated delivery of the machines and increased engineering and manufacturing costs primarily as a result of design changes. For 2023, the Company recorded a net favorable forward loss provision adjustment of$14.4 million. The favorable adjustment was the result of an amendment to the contract with Network Rail which extended the delivery schedule for the machines and reduced the estimate of liquidated damages. Partially offsetting this were higher estimated material, engineering and labor costs due to additional experience gained during the manufacturing process. It is possible there may be additional delays in the project requiring additional costs and liquidated damages to be recorded in the future, which could have a material impact on the Company's results in that period. For the Deutsche Bahn contract, the Company recorded additional loss provisions of $14.4 million during 2024, with $7.2 million recorded in the fourth quarter, related principally to unexpected supplier price increases, challenges with supplier quality on key components necessitating a switch to a different supplier and increased engineering efforts that exceeded previous estimates. During 2023, additional estimated forward loss provisions of $39.9 million were recorded. The main drivers of the additional forward loss provisions are increased estimated costs for components and engineering, as well as additional penalties recorded due to delivery delays. The increased costs include additional costs for new supply chain partners after a critical European-based supplier that filed for bankruptcy in 2022 had ceased operations during 2023. For the SBB contract, during the Company recorded net additional loss provisions of $2.2 million during 2024, with $2.7 million recorded in the fourth quarter related principally to increased estimates for assembly, storage and commissioning costs for the remaining vehicles due to project delays. For 2023, the Company recorded an additional estimated forward loss provision of $7.3 million due to increased estimates for material, engineering and commissioning costs. As of December 31, 2024, the contracts with Network Rail, Deutsche Bahn and SBB are 64%, 48% and 91% complete, respectively, based on costs incurred. The Company provides assurance type warranties primarily for product sales at Rail. 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.

Other Expenses

Other Expenses	12 Months Ended
	Dec. 31, 2024
Other Income and Expenses [Abstract]
Other Expenses	Other (Income) Expenses, Net The major components of this Consolidated Statements of Operations caption, broken out by operating segment, are as follows: (In thousands) 2024 2023 2022 Net gains Harsco Environmental Segment $ (3,357) $ (250) $ (1,869) Clean Earth Segment — — (1,512) Harsco Rail Segment — (2,311) — Corporate (3,272) — (632) Total net gains (6,629) (2,561) (4,013) Employee termination benefit costs Harsco Environmental Segment 6,013 1,977 4,998 Clean Earth Segment 521 1,399 1,786 Harsco Rail Segment 640 (645) 1,725 Corporate 1,179 275 (294) Total employee termination benefit costs 8,353 3,006 8,215 Other costs (income) to exit activities Harsco Environmental Segment (3,615) (7,810) 39 Clean Earth Segment — — — Harsco Rail Segment 9 3,576 4,003 Corporate 2,060 2,669 1,407 Total other costs (income) to exit activities (1,546) (1,565) 5,449 Asset impairments Harsco Environmental Segment 2,771 88 582 Clean Earth Segment 567 — 59 Harsco Rail Segment 1,921 — 95 Total asset impairments 5,259 88 736 Contingent consideration adjustments Clean Earth Segment — — (827) Corporate — (848) — Total contingent consideration adjustments — (848) (827) Other (income) expense — 289 2,094 Total other (income) expenses, net $ 5,437 $ (1,591) $ 11,654 Net Gains Net gains result from the sales of redundant properties (primarily land, buildings and related equipment) and non-core assets. In 2024, gains related to assets sold principally in Corporate primarily in North America and HE primarily in Latin America. In 2023, gains related to assets sold in Rail primarily in Asia Pacific. In 2022, gains related to assets sold principally in North America. Employee Termination Benefit Costs Costs and the related liabilities associated with involuntary termination benefit costs for one-time benefit arrangements provided as part of an exit or disposal activity are recognized when a formal plan for reorganization is approved at the appropriate level of management and is communicated to the affected employees. Additionally, costs associated with ongoing benefit arrangements, or in certain countries where statutory requirements dictate a minimum required benefit, are recognized when they are probable and estimable. The employee termination benefit costs in 2024 principally related to HE primarily in Latin America and Western Europe; and Corporate primarily in North America. The employee termination benefit costs in 2023 principally related to HE primarily in Western Europe and CE in North America. The employee termination benefit costs in 2022 related to HE primarily in Western Europe, Rail primarily in North America and CE in North America. Other Costs to Exit Activities Costs associated with exit or disposal activities include costs to terminate a contract and other costs associated with exit or disposal activities. Costs to terminate a contract are recognized when an entity terminates the contract or when an entity ceases using the right conveyed by the contract. This includes the costs to terminate the contract before the end of its term or the costs that will continue to be incurred under the contract for its remaining term without economic benefit to the entity. Other costs associated with exit or disposal activities (e.g., costs to sell a business, costs to consolidate or close facilities and relocate equipment or employees) are recognized and measured at their fair value in the period in which the liability is incurred. Also included are any benefits received in relation to an exit activity, such as a contract termination fee received from a customer. In 2024, exit costs were incurred in HE, mostly in Latin America. In 2023, exit income was incurred principally in HE, mostly due to a $8.1 million net gain in North America related to a lease modification that resulted in a lease incentive for the Company to relocate a site prior to the end of the expected lease term. In 2023 exit costs were incurred related to the Rail sale efforts. In 2022, exit costs were incurred principally related to the Rail sale efforts and in HE, mostly in Middle East/Africa. Asset Impairments Asset impairments include impairment charges for long-lived assets, other than definite-lived intangibles, and are measured as the amount by which the carrying amount of assets exceeds their fair value. Fair value is estimated based upon the expected future realizable discounted cash flows including anticipated selling prices. Non-cash impaired asset write-downs, for long-lived assets other than definite-lived intangibles, are included in Other, net, on the Consolidated Statements of Cash Flows as adjustments to reconcile net income (loss) to net cash provided by operating activities. In all years presented, impaired asset write-downs were incurred primarily in HE across several regions. In 2024, Rail had an impaired asset write-down in North America. Contingent Consideration Adjustments

Components of Accumulated Other

Components of Accumulated Other Comprehensive Loss	12 Months Ended
	Dec. 31, 2024
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Components of Accumulated Other Comprehensive Loss	Components of Accumulated Other Comprehensive Loss AOCI is included on the Consolidated Statements of Stockholders' Equity. The components of AOCI, net of the effect of income taxes, and activity for the years ended December 31, 2024 and 2023 are as follows: Components of AOCI - 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, 2022 $ (213,104) $ 157 $ (354,699) $ 10 $ (567,636) OCI before reclassifications 29,495 (a) 64 (b) (19,266) (c) 5 10,298 Amounts reclassified from AOCI, net of tax (507) (691) 18,225 — 17,027 Total OCI 28,988 (627) (1,041) 5 27,325 Less: OCI attributable to noncontrolling interests 617 — — — 617 OCI attributable to Enviri Corporation 29,605 (627) (1,041) 5 27,942 Balance at December 31, 2023 (183,499) (470) (355,740) 15 (539,694) OCI before reclassifications (46,316) (a) 7,036 (b) 24,133 (c) 7 (15,140) Amounts reclassified from AOCI, net of tax (108) (2,797) 17,550 — 14,645 Total OCI (46,424) 4,239 41,683 7 $ (495) Less: OCI attributable to noncontrolling interests 1,225 — — — 1,225 OCI attributable to Enviri Corporation (45,199) 4,239 41,683 7 730 Balance at December 31, 2024 $ (228,698) $ 3,769 $ (314,057) $ 22 $ (538,964) (a) Principally foreign currency fluctuation. (b) Principally net change from periodic revaluations. (c) Principally changes due to annual actuarial remeasurements and foreign currency translation. Amounts reclassified from AOCI for 2024 and 2023 are as follows: Year Ended December 31, 2024 Year Ended December 31, 2023 Affected Caption on the (In thousands) Amortization of defined benefit pension items (d) : Actuarial losses $ 19,239 $ 18,917 Defined benefit pension income (expense) Prior-service costs 492 520 Defined benefit pension income (expense) Settlement/curtailment gain (1,125) (42) Defined benefit pension income (expense) Total before tax 18,606 19,395 Tax benefit (1,056) (1,170) Total reclassification of defined benefit pension items, net of tax $ 17,550 $ 18,225 Amortization of cash flow hedging instruments (e) : Foreign currency exchange forward contracts $ (695) $ 1,638 Product revenues Interest rate swaps (3,018) (2,576) Interest expense Total before tax (3,713) (938) Tax benefit 916 247 Total reclassification of cash flow hedging instruments $ (2,797) $ (691) Recognition of cumulative foreign exchange translation adjustments: Gain on substantial liquidation of subsidiaries (f) $ (108) $ (507) Other (income) expenses, net Total reclassification of cumulative foreign exchange translation adjustments $ (108) $ (507) (d) These AOCI components are included in the computation of NPPC. See Note 10, Employee Benefit Plans, for additional information. (e) See Note 15, Financial Instruments for additional information.

SCHEDULE II. VALUATION AND QUAL

SCHEDULE II. VALUATION AND QUALIFYING ACCOUNTS	12 Months Ended
	Dec. 31, 2024
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]
SCHEDULE II. VALUATION AND QUALIFYING ACCOUNTS	SCHEDULE II. VALUATION AND QUALIFYING ACCOUNTS Continuing Operations (In thousands) Additions (Deductions) Description Balance at Charged to Foreign Currency Translation Adjustments Other Balance at End For the year ending December 31, 2024: Allowance for Expected Credit Losses $ 15,522 $ 2,821 $ (117) $ (3,112) (a) $ 15,114 Deferred Tax Assets—Valuation Allowance 177,888 27,317 (7,240) (5,220) (b) 192,745 For the year ending December 31, 2023: Allowance for Expected Credit Losses $ 8,853 $ 7,042 $ (37) $ (336) (a) $ 15,522 Deferred Tax Assets—Valuation Allowance 132,954 44,608 3,721 (3,395) (b) 177,888 For the year ending December 31, 2022: Allowance for Expected Credit Losses $ 12,235 $ 330 $ (110) $ (3,602) (a) $ 8,853 Deferred Tax Assets—Valuation Allowance 130,902 21,505 (8,625) (10,828) (b) 132,954 (a) Includes the write-off of, net of collections, on previously reserved accounts receivable balances and changes in credit memo reserves reflected as adjustments to revenue. (b) 2024 includes decreases of $5.4 million related to pension adjustments recorded through AOCI. 2023 included decreases of $1.8 million related to pension adjustments recorded through AOCI and $1.8 million related to state tax rate reductions and state NOL expirations in the U.S. 2022 included a decrease of $7.1 million related to pension adjustments recorded through AOCI and $4.3 million related to state tax rate reductions and state NOL expirations in the U.S.

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Pay vs Performance Disclosure
Net income (loss) attributable to Enviri Corporation common stockholders	$ (127,973)	$ (86,121)	$ (180,069)

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Dec. 31, 2024
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Insider Trading Policies and Pr

Insider Trading Policies and Procedures	12 Months Ended
	Dec. 31, 2024
Insider Trading Policies and Procedures [Line Items]
Insider Trading Policies and Procedures Adopted	true

Cybersecurity Risk Management a

Cybersecurity Risk Management and Strategy Disclosure	12 Months Ended
	Dec. 31, 2024
Cybersecurity Risk Management, Strategy, and Governance [Line Items]
Cybersecurity Risk Management Processes for Assessing, Identifying, and Managing Threats [Text Block]	The Company’s cybersecurity program is designed to detect cybersecurity threats and vulnerabilities, protect the Company’s information systems from such threats, and ensure the confidentiality, integrity, and availability of systems and information used, owned or managed by the Company. The Company places special weight on protecting sensitive information, such as personal information of the Company’s customers and employees, and confidential business information that could be leveraged by a competitor or a malicious actor. The Company’s cybersecurity program comprises several components, including the adoption of information security protocols, standards, and guidelines consistent with industry best practices; engaging third-party service providers to conduct security assessments and penetration testing; and performing periodic internal audits of the Company’s cybersecurity protocols. The Company employs a risk-based process designed to manage cybersecurity risk presented by third-party vendors that may have access to the Company's sensitive information and/or information technology ("IT") systems. This process may consider the nature of the services provided, the sensitivity and quantity of information processed, the criticality of any potentially impacted IT systems, and/or the strength of the vendor’s cybersecurity practices. The Company monitors potential cybersecurity risks through an enterprise risk “heatmap” that tracks key cybersecurity risks at divisional and enterprise levels. These key risks are characterized by various factors such as the likelihood of the Company experiencing a particular type of cybersecurity incident, the speed at which each type of cybersecurity incident could impact the Company, and management’s assessment of the Company’s ability to respond quickly and efficiently. An incident response plan (“Incident Response Plan”) aligned with best practices articulated by the National Institute of Standards and Technology (“NIST”) governs the Company’s response to cybersecurity incidents. This Incident Response Plan outlines how the Company detects, analyzes, contains, eradicates, recovers, and performs post-incident activities in the event of a cybersecurity incident. It also contains an internal, risk-based escalation framework designed to ensure that all relevant individuals are promptly informed of any cybersecurity incident and dictates procedures for determining whether a cybersecurity incident is material without unreasonable delay. MATERIAL EFFECTS FROM RISKS OF CYBERSECURITY THREATS
Cybersecurity Risk Management Processes Integrated [Flag]	true
Cybersecurity Risk Management Processes Integrated [Text Block]	The Company’s cybersecurity program is designed to detect cybersecurity threats and vulnerabilities, protect the Company’s information systems from such threats, and ensure the confidentiality, integrity, and availability of systems and information used, owned or managed by the Company. The Company places special weight on protecting sensitive information, such as personal information of the Company’s customers and employees, and confidential business information that could be leveraged by a competitor or a malicious actor.
Cybersecurity Risk Management Third Party Engaged [Flag]	true
Cybersecurity Risk Third Party Oversight and Identification Processes [Flag]	true
Cybersecurity Risk Materially Affected or Reasonably Likely to Materially Affect Registrant [Flag]	false
Cybersecurity Risk Board of Directors Oversight [Text Block]	The Board has delegated responsibility for overseeing the Company’s cybersecurity and information technology processes to the Audit Committee.
Cybersecurity Risk Board Committee or Subcommittee Responsible for Oversight [Text Block]	The Audit Committee is responsible for overseeing the implementation and effectiveness of the Company’s processes and risk management protocols regarding cybersecurity and information technology, including risks from cybersecurity incidents and vulnerabilities and third-party service providers, and the steps taken by Mr. Tipler and the IT security department to inform themselves about and monitor the prevention, detection, mitigation, and remediation of such risks.
Cybersecurity Risk Process for Informing Board Committee or Subcommittee Responsible for Oversight [Text Block]	Mr. Tipler reports to the Audit Committee regarding material cybersecurity incidents and any remediation efforts and is also responsible for providing quarterly updates regarding the overall effectiveness of the Company’s cybersecurity program.
Cybersecurity Risk Role of Management [Text Block]	The Company’s Vice President, Chief Information Security Officer and Corporate IT, Giles Tipler, oversees the Company’s IT security department and is responsible for assessing and managing cybersecurity risks and for leading the Company’s response to cybersecurity incidents. Mr. Tipler has over 25 years of experience in information security, risk management, compliance, and information technology, with significant experience building cybersecurity programs across multiple countries in the Americas, Europe, the Middle East, Africa, and the Asia-Pacific regions. Mr. Tipler played an instrumental role in the development of the Company’s Incident Response Plan and reports to the Company’s Chief Financial Officer, Mr. Tom Vadaketh. Mr. Tipler is also responsible for providing quarterly updates to the Company’s Audit Committee and Board of Directors regarding enterprise level risks, the effectiveness of the Company’s cybersecurity program, and any material cybersecurity incidents that may arise.
Cybersecurity Risk Management Positions or Committees Responsible [Flag]	true
Cybersecurity Risk Management Positions or Committees Responsible [Text Block]	The Company’s Vice President, Chief Information Security Officer and Corporate IT, Giles Tipler, oversees the Company’s IT security department and is responsible for assessing and managing cybersecurity risks and for leading the Company’s response to cybersecurity incidents.
Cybersecurity Risk Management Expertise of Management Responsible [Text Block]	Mr. Tipler has over 25 years of experience in information security, risk management, compliance, and information technology, with significant experience building cybersecurity programs across multiple countries in the Americas, Europe, the Middle East, Africa, and the Asia-Pacific regions.
Cybersecurity Risk Process for Informing Management or Committees Responsible [Text Block]	Mr. Tipler is also responsible for providing quarterly updates to the Company’s Audit Committee and Board of Directors regarding enterprise level risks, the effectiveness of the Company’s cybersecurity program, and any material cybersecurity incidents that may arise.
Cybersecurity Risk Management Positions or Committees Responsible Report to Board [Flag]	true

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2024
Accounting Policies [Abstract]
Consolidation	Consolidation
Reclassifications	Reclassifications During the year ended December 31, 2024, the Company determined that the held-for-sale criteria for Rail was no longer met and, as a result, the Company made reclassifications to prior year amounts previously classified as discontinued operations and assets held-for-sale in the Company's Consolidated Statements of Operations and Consolidated Balance Sheets, along with the accompanying notes to the Company's Consolidated Financial Statements. See Note 3, Discontinued Operations and Dispositions for further details. Other reclassifications have been made to prior year amounts to conform with current year classifications. These reclassifications did not have a material impact on the Company's Consolidated Financial Statements, including the notes thereto.
Cash and Cash Equivalents	Cash and Cash Equivalents Cash and cash equivalents include cash on hand, demand deposits and short-term investments that are highly liquid in nature and have an original maturity of three months or less.
Restricted Cash	Restricted Cash The Company had restricted cash of $1.8 million and $3.4 million at December 31, 2024 and 2023, respectively, and the restrictions are primarily related to collateral provided for certain guarantees of the Company’s performance.
Accounts Receivable	Accounts Receivable Accounts receivable are stated at net realizable value, which represents the face value of the receivable, less an allowance for expected credit losses. The allowance for expected credit losses is maintained for expected lifetime losses resulting from the inability of customers to make required payments. The Company’s expected credit loss allowance methodology for accounts receivable is developed using historical collection experience, current and future economic and market conditions and a review of the current status of customers' trade accounts receivables. When required, the Company adjusts the loss-rate methodology to account for current conditions and reasonable and supportable expectations of future economic and market conditions. The Company generally assesses future economic conditions for a period which corresponds with the contractual life of its accounts receivable. Additionally, specific allowance amounts are established to record the appropriate provision for customers that have a higher probability of default.
Inventories	Inventories Inventories are accounted for using the average cost, first-in, first-out ("FIFO") or last-in, first-out ("LIFO") method. Inventory accounted for under the average cost and FIFO methods are stated at the lower of cost or net realizable value. Inventory accounted for under the LIFO method is stated at the lower of cost or market. See Note 5, Inventories
Depreciation	Property, Plant and Equipment Property, plant and equipment ("PP&E") is recorded at cost and depreciated over the estimated useful lives of the assets using, principally, the straight-line method. When PP&E is retired from service, the cost of the retirement is charged to the allowance for depreciation to the extent of the accumulated depreciation and the balance is charged to income. Long-lived assets to be disposed of by sale are not depreciated while they are classified as held-for-sale.
Leases	Leases The Company leases certain property and equipment under noncancelable lease agreements. The Company determines if a contract or arrangement contains a lease at inception. All leases are evaluated and classified as either an operating or finance lease. A lease is classified as a finance lease if any of the following criteria are met: (i) ownership of the underlying asset transfers to the Company by the end of the lease term; (ii) the lease contains an option to purchase the underlying asset that the Company is reasonably expected to exercise; (iii) the lease term is for a major part of the remaining economic life of the underlying asset; (iv) the present value of the sum of lease payments and any residual value guaranteed by the Company equals or exceeds substantially all of the fair value of the underlying asset; or (v) the underlying asset is of a specialized nature that it is expected to have no alternative use to the lessor at the end of the lease term. A lease that does not meet any of the finance lease classification criteria is classified as an operating lease. Operating leases are included as Right-of-use assets, net, Current portion of operating lease liabilities, and Operating lease liabilities on the Consolidated Balance Sheets. ROU assets and operating lease liabilities are recognized based on the present value of the future lease payments over the lease term at the commencement date. As most of the Company’s leases do not provide an implicit rate for use in determining the present value of future payments, the Company uses an incremental borrowing rate. This incremental borrowing rate reflects the creditworthiness of the Company for a lending period commensurate to the term of the lease, the standard lending practices related to such loans in the respective jurisdiction where the underlying assets are located and the local currency in which the lease is denominated. ROU assets also include any lease payments made prior to or at the lease commencement date and initial direct costs incurred, and may be reduced by any lease incentives received by the lessor. Lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Lease expense for minimum lease payments is recognized on a straight-line basis over the lease term, including rent abatement periods and rent holidays. Certain of the Company's leases are subject to annual changes in an index or are subject to adjustments for which the amounts are not readily determinable at lease inception. While lease liabilities are not remeasured as a result of changes to these costs, changes are treated as variable lease payments and recognized in the period in which the obligation for those payments were incurred. Finance leases are included as PP&E, net; Current maturities of long-term debt and Long-term debt on the Consolidated Balance Sheets. Finance lease costs are split between depreciation expense related to the asset and interest expense on the lease liability, using the effective rate charged by the lessor. Note 8, Debt and Credit Agreements Note 9, Leases
Goodwill and Other Intangible Assets	Goodwill In accordance with U.S. GAAP, goodwill is not amortized and is tested for impairment at least annually or more frequently if indicators of impairment exist or if a decision is made to dispose of a business. Goodwill is assigned among and evaluated for impairment at the reporting unit level, which is defined as an operating segment or one level below an operating segment for which discrete financial information is available. A significant amount of judgment is involved in determining if an indicator of impairment has occurred. Such indicators may include declining cash flows or operating losses at the reporting unit level, a significant adverse change in legal factors or in the business climate, an adverse action or assessment by a regulator, unanticipated competition, a loss of key personnel or a more likely than not expectation that a reporting unit or a significant portion of a reporting unit will be sold or otherwise disposed of, among others. In applying the goodwill impairment test, the Company has the option to perform a qualitative test, a quantitative test or both. Under the qualitative test, the Company assesses qualitative factors to determine whether it is more likely than not that the fair value of the reporting units is less than its carrying value. Qualitative factors may include, but are not limited to, economic conditions, industry and market considerations, cost factors, overall financial performance of the reporting unit and other entity and reporting unit specific events. If after assessing these qualitative factors, the Company determines it is “more-likely-than-not” that the fair value of the reporting unit is less than the carrying value, the Company would perform a quantitative test. Note 7, Goodwill and Other Intangible Assets
Impairment of Long-Lived Assets (Other than Goodwill)	Long-Lived Assets Impairments (Other than Goodwill)
Deferred Financing Costs	Deferred Financing Costs The Company has incurred debt issuance costs, which are recognized as a reduction of Long-term debt on the Consolidated Balance Sheets. Debt issuance costs are amortized and recognized over the contractual term of the related indebtedness or shorter period, if appropriate, based upon contractual terms in Interest expense on the Consolidated Statements of Operations. Whenever indebtedness is modified from its original terms, an evaluation is made whether an accounting modification or extinguishment has occurred in order to determine the accounting treatment for debt issuance costs related to the debt modification. If the evaluation results in a gain (loss) on extinguishment of debt, the amount would be included in Facility fees and debt-related income (expense) on the Consolidated Statements of Operations. If the evaluation results in a modification of debt, unamortized costs would be amortized over the new contractual term.
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. Total revenues include service revenues from the Company's HE, CE and Rail segments and product revenues from the Company's HE and Rail segments. Harsco Environmental - HE provides on-site services, under long-term contracts which may contain multiple performance obligations for material logistics, product quality improvement and resource recovery from iron, steel and metals manufacturing, and the production of aluminum dross and scrap processing systems. • 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, including 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, which is typically 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. • Product revenues in the aluminum dross and scrap process systems business are generally recognized over time as control is transferred to the customer. Control transfers over time because aluminum dross and scrap systems 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 ("cost-to-cost method") 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. Clean Earth - This Segment provides specialty waste processing and beneficial reuse solutions for hazardous wastes, and soil and dredged materials. • 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 the amount of materials received for processing 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 principally variable based on volume and recognized as services are performed. Amounts are typically billed and payable on a monthly basis. Harsco Rail - This business sells railway track maintenance equipment, after-market parts and safety and diagnostic equipment and provides railway track maintenance services. Certain contracts may contain multiple performance obligations, such as a sale of equipment with services and spare parts. • For standard 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. Rail uses the cost-to-cost method to measure progress because it is the measure that best depicts the transfer of control to the customer, which occurs as costs are incurred under the contracts. Under the cost-to-cost method, the extent of progress towards completion is based on the ratio of costs incurred to total estimated costs at completion, which includes both actual costs already incurred and the estimated costs to complete. Accounting for contracts with customers using the cost-to-cost method requires significant judgment relative to assessing risks, which may include estimating contract revenues (including estimates of variable consideration, if applicable, as well as estimating any liquidating damages or penalties related to performance), estimating contract costs (including estimating engineering costs to design the machine and the material, labor and overhead manufacturing costs to build the machine), making assumptions for schedule and technical items, properly executing the engineering and design phases consistent with customer expectations; the availability and costs of labor and material resources, productivity and evaluating whether a significant financing component is present. Due to the number of years it may take to complete certain contracts and the scope and nature of the work required to be performed on those contracts, estimating total revenues and costs at completion is inherently complicated and subject to many variables. 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. Railway track maintenance equipment revenue of approximately $48.5 million, $70.9 million and $49.6 million was recognized using the cost-to-cost method in 2024, 2023, and 2022, respectively. • For after-market parts sales and safety and diagnostics equipment, revenue is recognized at the point when control transfers to the customer. Control generally transfers 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, including footage, 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. The Company has elected to utilize the following practical expedients on an ongoing basis: • 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 in Note 17, Revenue Recognition is limited to the fixed portion of fees related to revenues from services and products in HE and Rail. Taxes assessed by governmental authorities that are both imposed on and concurrent with a specific revenue-producing transaction, that are collected by the Company from a customer, are excluded from revenue. Additionally, in certain contracts, the Company facilitates shipping and handling activities after control has transferred to the customer. The Company has elected to record all shipping and handling activities as costs to fulfill a contract. In situations where the shipping and handling costs have not been incurred at the time revenue is recognized, the respective shipping and handling costs are accrued.
Income Taxes	Income Taxes The Company accounts for income taxes under the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of the events that have been included in the consolidated financial statements. Under this method, deferred tax assets and liabilities are determined based on the differences between the consolidated financial statements and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in income in the period that includes the enactment date. The Company records deferred tax assets to the extent that the Company believes that these assets will more likely than not be realized. In making such determinations, the Company considers all available positive and negative evidence, including future reversals of existing deferred tax liabilities, projected future taxable income, tax planning strategies and recent financial results. If the Company determines that it will not be able to realize deferred income tax assets in the future, a valuation allowance is recorded. If sufficient positive evidence arises in the future indicating that all or a portion of the deferred tax assets meet the more likely than not standard for realization, the valuation allowance would be reduced accordingly in the period that such a conclusion is reached. The Company prepares and files tax returns based on interpretation of tax laws and regulations and records its provision for income taxes based on these interpretations. Uncertainties may exist in estimating the Company's tax provisions and in filing tax returns in the many jurisdictions in which the Company operates, and as a result these interpretations may give rise to an uncertain tax position. The tax benefit from an uncertain tax position is recognized when it is more likely than not that the position will be sustained upon examination, including resolutions of any related appeals or litigation processes, based on its technical merits. Each subsequent period, the Company determines if existing or new uncertain tax positions meet a more likely than not recognition threshold and adjusts accordingly. The Company recognizes interest and penalties related to unrecognized tax benefits within Income tax expense in the accompanying Consolidated Statements of Operations. Liabilities for uncertain tax positions are included in Other liabilities on the Consolidated Balance Sheets. The significant assumptions and estimates described in the preceding paragraphs are important contributors to the effective tax rate each year.
Accrued Insurance and Loss Reserves	Accrued Insurance and Loss Reserves The Company retains a significant portion of the risk for certain U.S. workers' compensation, U.K. employers' liability, automobile, general and product liability losses. Insurance reserves have been recorded that reflect the undiscounted estimated liabilities including claims incurred but not reported. When a recognized liability is covered by third-party insurance, the Company records an insurance claim receivable to reflect the covered liability. Changes in the estimates of the reserves are included in net income (loss) in the period determined. During the years ended December 31, 2024, 2023 and 2022, the Company recorded insurance reserve adjustments that increased (decreased) pre-tax insurance expense from continuing operations for self-insured programs by $(1.1) million $1.6 million and $(1.6) million, respectively. At December 31, 2024 and 2023, the Company has recorded liabilities of $30.3 million and $32.5 million, respectively, related to both asserted as well as unasserted insurance claims. Included in the balances at December 31, 2024 and 2023 were $5.9 million and $6.5 million, respectively, of recognized liabilities covered by insurance carriers. Amounts estimated to be paid within one year have been included in Other current liabilities, with the remainder included in Other liabilities on the Company's Consolidated Balance Sheets.
Foreign Currency Translation	Foreign Currency Translation
Financial Instruments and Hedging	Financial Instruments and Hedging The Company has operations throughout the world that are exposed to fluctuations in related foreign currencies in the normal course of business. The Company seeks to reduce exposure to foreign currency fluctuations through the use of forward exchange contracts. The Company does not hold or issue financial instruments for trading purposes, and it is the Company's policy to prohibit the use of derivatives for speculative purposes. The Company has a Foreign Currency Risk Management Committee that meets periodically to monitor foreign currency risks. The Company executes foreign currency exchange forward contracts to hedge transactions for firm purchase commitments, to hedge variable cash flows of forecasted transactions and for export sales denominated in foreign currencies. These contracts are generally for 90 days or less; however, where appropriate, longer-term contracts may be utilized. For those contracts that are designated as qualified cash flow hedges, gains or losses are recorded in AOCI on the Consolidated Balance Sheets. The Company uses interest rate swaps in conjunction with certain debt issuances in order to secure a fixed interest rate. The interest rate swaps are recorded on the Consolidated Balance Sheets at fair value, with changes in value attributed to the effect of the swaps’ interest spread and changes in the credit worthiness of the counter-parties recorded in AOCI. Amounts recorded in AOCI on the Consolidated Balance Sheets are reclassified into income in the same period or periods during which the hedged forecasted transaction affects income. The cash flows from these contracts are classified consistent with the cash flows from the transaction being hedged (e.g., the cash flows related to contracts to hedge the purchase of fixed assets are included in cash flows from investing activities, etc.). The Company also enters into certain forward exchange contracts that are not designated as hedges. Gains and losses on these contracts are recognized in the Consolidated Statements of Operations based on changes in fair market value. For fair value hedges of a firm commitment, the gain or loss on the derivative and the offsetting gain or loss on the hedged firm commitment are recognized concurrently in the Consolidated Statements of Operations.
Earnings Per Share	Earnings Per Share
Use of Estimates in the Preparation of Financial Statements	Use of Estimates in the Preparation of Financial Statements The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses. Actual results could differ from those estimates.
Recently Adopted and Recently Issued Accounting Standards	Recently Adopted and Recently Issued Accounting Standards The following accounting standards were adopted in 2024: For the year ended December 31, 2024, the Company adopted changes issued by the FASB that require expansion of annual and interim disclosure requirements for reportable segments. The changes require additional interim and annual disclosures regarding segment profit (loss) measures that are regularly reviewed by the chief operating decision maker, which include significant segment expenses and other segment items that are included in the reported segment profit (loss), segment asset information and a reconciliation of the reportable segment amounts for each profit (loss) measure to the corresponding amounts on an entity's consolidated financial statements. This change also requires additional annual disclosures for other qualitative information related to the chief operating decision maker and how the reported measures are used by him. The adoption of these changes did not have any material impact on the Company's Consolidated Financial Statements. See Note 16, Information by Segment and Geographic Area for details. The following accounting standards have been issued and become effective for the Company at a future date: In December 2023, the FASB issued changes which require greater disaggregation of income tax disclosures related to the income tax rate reconciliation and income taxes paid. The changes become effective starting with the Company's annual financial statements for the year ended December 31, 2025. The guidance should be applied on a prospective basis with the option to apply the standard retrospectively. Early adoption is permitted. The Company is currently evaluating the impact that this change will have on the Company's disclosures. In November 2024, the FASB issued changes which requires disaggregated disclosure of income statement expenses within the footnotes to the financial statement for each interim and annual reporting period. The changes become effective starting with the Company's annual financial statements for the year ended December 31, 2027 and will be in effect for the Company's interim financial statements after December 31, 2027. The guidance should be applied on a prospective basis with the option to apply the standard retrospectively. Early adoption is permitted. The Company is currently evaluating the impact that this change will have on the Company's disclosures.

Discontinued Operations (Tables

Discontinued Operations (Tables)	12 Months Ended
	Dec. 31, 2024
Business Combinations [Abstract]
Disposal Groups, Including Discontinued Operations	(in thousands) December 31 Trade accounts receivable, net $ 57,415 Other receivables 6,708 Inventories 103,077 Current portion of contract assets 56,341 Prepaid expenses 28,797 Other current assets 2,895 Property, plant and equipment, net 44,113 Right-of-use assets, net 7,050 Goodwill 13,026 Intangible assets, net 3,122 Retirement plan assets 344 Deferred income tax assets 973 Other assets 22,448 Total assets $ 346,309 Accounts payable $ 44,703 Accrued compensation 6,056 Income taxes payable 1,434 Current portion of operating lease liabilities 3,656 Current portion of advances on contracts 32,912 Reserve for contracts 52,725 Other current liabilities 30,550 Operating lease liabilities 3,331 Deferred tax liabilities 350 Other liabilities 494 Total liabilities $ 176,211 Years Ended December 31 (In thousands) 2023 2022 Service revenues $ 52,430 $ 29,331 Product revenues 244,365 215,585 Total revenues 296,795 244,916 Cost of services sold 34,552 19,550 Cost of products sold 247,917 223,034 Total cost of sales 282,469 242,584 Selling, general and administrative expenses 41,602 36,799 Research and development expenses 2,172 2,168 Other expense (income) net 1,628 6,917 Total costs and expenses 327,871 288,468 Operating income (loss) from continuing operations (31,076) (43,552) Interest income 139 270 Interest expense (3,209) (1,651) Defined benefit pension income (expense) 26 (5) Income (loss) from continuing operations before taxes and equity income (34,120) (44,938) Income tax benefit (expense) from continuing operations (2,681) 5,525 Income (loss) from continuing operations $ (36,801) $ (39,413) Harsco Environmental Segment On April 1, 2024, the Company completed the sale of Performix, a subsidiary of HE, for $17.5 million, subject to normal post-closing adjustments, and recognized a gain on the sale of $1.8 million (or approximately $1.3 million after-tax). The most material classes of assets on the date of the sale were Accounts receivable of $4.7 million and Goodwill of $5.3 million. On August 29, 2024, the Company completed the sale of Reed, a subsidiary of HE, for $45.0 million subject to normal post-closing adjustments, and recognized a gain on sale of $8.7 million (or approximately $2.8 million after-tax). The most material classes of assets and liabilities on the date of the sale were Trade accounts receivable, net of $9.9 million, Inventories of $7.1 million, Property, plant and equipment ("PP&E") net of $10.7 million, Goodwill of $13.7 million and Accounts payable of $6.9 million. Other

Accounts Receivable and Note _2

Accounts Receivable and Note Receivable (Tables)	12 Months Ended
	Dec. 31, 2024
Receivables [Abstract]
Schedule of accounts receivable	Accounts receivable consist of the following: (In thousands) December 31 December 31 Trade accounts receivable $ 275,804 $ 353,709 Less: Allowance for expected credit losses (15,114) (15,522) Trade accounts receivable, net $ 260,690 $ 338,187 Other receivables (a) $ 40,439 $ 40,565 (a) Other receivables include employee receivables, insurance receivable, tax claims and refunds and other miscellaneous receivables not included in Trade accounts receivable, net. (In millions) December 31 December 31 Net amounts sold under factoring arrangements $ 13.3 $ 16.1 Program capacities 18.6 32.6 (In millions) December 31 December 31 Note receivable, at amortized cost $ — $ 14.0 Note receivable, at fair value — 15.4
Schedule of provision for doubtful accounts related to trade accounts receivable	The provision for expected credit losses related to trade accounts receivable was as follows: Years Ended December 31 (In thousands) 2024 2023 2022 Change in provision for expected credit losses $ 2,821 $ 7,042 $ 330

Inventories (Tables)

Inventories (Tables)	12 Months Ended
	Dec. 31, 2024
Inventory Disclosure [Abstract]
Schedule of inventories	Inventories consist of the following: (In thousands) December 31 December 31 Finished goods $ 14,344 $ 16,171 Work-in-process 15,629 13,081 Raw materials and purchased parts 107,364 114,046 Stores and supplies 44,705 46,071 Total inventories $ 182,042 $ 189,369 Valued at lower of cost or market: LIFO basis $ 96,680 $ 95,203 FIFO basis 18,747 18,685 Average cost basis 66,615 75,481 Total inventories $ 182,042 $ 189,369

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	12 Months Ended
	Dec. 31, 2024
Property, Plant and Equipment [Abstract]
Schedule of property, plant and equipment	PP&E consist of the following: (In thousands) Estimated December 31 December 31 Land and improvements 5-20 years $ 94,551 $ 93,793 Buildings and improvements (a) 10-30 years 225,688 243,472 Machinery and equipment (b) 3-20 years 1,576,298 1,729,637 Uncompleted construction — 53,441 66,241 Gross property, plant and equipment 1,949,978 2,133,143 Less: Accumulated depreciation (1,285,686) (1,425,746) Property, plant and equipment, net $ 664,292 $ 707,397 (a) Buildings and improvements include leasehold improvements that are amortized over the shorter of their useful lives or the term of the lease. (b) Includes information technology hardware and software.

Goodwill and Other Intangible_2

Goodwill and Other Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2024
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill	The following table reflects the changes in carrying amounts of goodwill by each reporting unit for the years ended December 31, 2024 and 2023: (In thousands) Harsco Environmental Clean Earth Harsco Rail Consolidated Totals Balance at December 31, 2022 $ 379,954 $ 379,299 $ 13,026 $ 772,279 Foreign currency translation 8,699 — — 8,699 Balance at December 31, 2023 388,653 379,299 13,026 780,978 Changes to goodwill (a) (19,031) — — (19,031) Goodwill impairment — — (13,026) (13,026) Foreign currency translation (9,163) — — (9,163) Balance at December 31, 2024 $ 360,459 $ 379,299 $ — $ 739,758 (a) The changes to goodwill relate to the divestitures of the Performix and Reed businesses.
Schedule of Acquired Finite-Lived Intangible Assets by Major Class	The following table reflects these intangible assets by major category: December 31, 2024 December 31, 2023 (In thousands) Gross Carrying Accumulated Gross Carrying Accumulated Customer related $ 95,251 $ 69,795 $ 102,119 $ 66,016 Permits 310,236 82,799 309,679 66,733 Technology related 22,880 17,477 21,803 17,001 Trade names 31,514 15,142 31,580 12,428 Air rights 26,139 3,979 26,139 3,281 Patents 162 148 206 179 Non-compete agreement 2,500 2,500 2,500 2,343 Other 3,457 1,861 3,584 1,646 Total $ 492,139 $ 193,701 $ 497,610 $ 169,627
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense	The following table shows the estimated amortization expense for the next five fiscal years based on current intangible assets. (In thousands) 2025 2026 2027 2028 2029 Estimated amortization expense (a) $ 26,300 $ 26,300 $ 25,000 $ 23,500 $ 22,800 (a) These estimated amortization expense amounts do not reflect the potential effect of future foreign currency exchange rate fluctuations.

Debt and Credit Agreements (Tab

Debt and Credit Agreements (Tables)	12 Months Ended
	Dec. 31, 2024
Debt Disclosure [Abstract]
Schedule of Line of Credit Facilities	The following table shows the amount outstanding under the Revolving Credit Facility and available credit at December 31, 2024. December 31, 2024 (In thousands) Facility Outstanding Outstanding Letters of Credit Available Revolving Credit Facility $ 675,000 $ 407,000 $ 29,846 $ 238,154
Schedule of Long-term Debt Instruments	The Company's long-term debt consists of the following: (In thousands) December 31 December 31 Senior Secured Credit Facilities (a) : Term Loan with an interest rate of 6.72% and 7.72% at December 31, 2024 and 2023, respectively $ 482,500 $ 487,500 Revolving Credit Facility with an average interest rate of 6.49% and 8.12% at December 31, 2024 and 2023, respectively 407,000 422,000 5.75% Senior Notes 475,000 475,000 Other financing payable (including finance leases) in varying amounts due principally through 2030 with a weighted-average interest rate of 7.14% and 6.11% at December 31, 2024 and 2023, respectively 79,917 44,469 Total debt obligations 1,444,417 1,428,969 Less: deferred financing costs (12,695) (11,974) Total debt obligations, net of deferred financing costs 1,431,722 1,416,995 Less: current maturities of long-term debt (21,004) (15,558) Long-term debt $ 1,410,718 $ 1,401,437 (a) The current portion of long-term debt related to the Senior Secured Credit Facilities was $5.0 million with the remainder reflected as Long-term debt at December 31, 2024 and 2023.
Schedule of Maturities of Long-term Debt	The maturities of long-term debt for the four years following December 31, 2025 are as follows: (In thousands) 2026 $ 50,019 2027 494,421 2028 480,873 2029 387,026
Schedule Of Facility Fees And Debt-Related Income (Expense)	The components of the Consolidated Statements of Operations caption Facility fees and debt-related income (expense) were as follows: Years Ended December 31 (In thousands) 2024 2023 2022 Gain (loss) on extinguishment of debt $ (325) $ — $ 2,254 Unused debt commitment and amendment fees — (12) (1,696) Securitization and factoring fees (10,940) (10,750) (3,514) Facility fees and debt-related income (expense) $ (11,265) $ (10,762) $ (2,956)

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2024
Leases [Abstract]
Lease, Cost [Table Text Block]	The components of lease expense were as follows: (In thousands) 2024 2023 2022 Finance leases: Depreciation expense $ 12,785 $ 7,957 $ 3,938 Interest on lease liabilities 4,318 2,036 784 Operating leases 38,702 38,062 35,290 Variable and short-term leases 54,475 54,432 52,050 Sublease income (7) (7) (6) Total lease expense $ 110,273 $ 102,480 $ 92,056 Supplemental cash flow information related to leases was as follows: (In thousands) 2024 2023 2022 Cash paid for amounts included in the measurement of lease liabilities: Cash flows used by operating activities - Operating leases $ 37,120 $ 37,880 $ 34,420 Cash flows used by operating activities - Finance leases 4,203 1,914 798 Cash flows used by financing activities - Finance leases 12,316 7,736 3,975 ROU assets obtained in exchange for lease obligations: Operating leases $ 21,895 $ 27,951 $ 32,817 Finance leases 49,316 27,128 11,175 Supplemental balance sheet information related to leases was as follows: (In thousands) 2024 2023 Operating Leases: Operating lease ROU assets $ 92,153 $ 102,891 Current portion of operating lease liabilities 26,049 28,775 Operating lease liabilities 67,998 75,476 Finance Leases: Property, plant and equipment, net $ 73,734 $ 43,151 Current maturities of long-term debt 16,004 9,723 Long-term debt 63,913 33,911 Supplemental additional information related to leases was as follows: 2024 2023 Other information: Weighted average remaining lease term - Operating leases (in years) 6.98 7.03 Weighted average remaining lease term - Finance leases (in years) 5.27 5.33 Weighted average incremental borrowing rate - Operating leases 6.7 % 6.3 % Weighted average incremental borrowing rate - Finance leases 7.2 % 6.4 %
Lessee, Operating Lease, Liability, Maturity [Table Text Block]	Maturities of lease liabilities were as follows: (In thousands) Operating Leases Finance Leases Year Ending December 31: 2025 $ 32,934 $ 20,998 2026 25,516 19,462 2027 18,456 17,488 2028 12,803 15,525 2029 8,724 10,938 After 2029 41,883 11,805 Total lease payments 140,316 96,216 Less: Imputed interest (32,030) (16,299) Total lease liabilities (a) $ 108,286 $ 79,917
Finance Lease, Liability, Maturity [Table Text Block]	Maturities of lease liabilities were as follows: (In thousands) Operating Leases Finance Leases Year Ending December 31: 2025 $ 32,934 $ 20,998 2026 25,516 19,462 2027 18,456 17,488 2028 12,803 15,525 2029 8,724 10,938 After 2029 41,883 11,805 Total lease payments 140,316 96,216 Less: Imputed interest (32,030) (16,299) Total lease liabilities (a) $ 108,286 $ 79,917 (a) Includes payments for operating leases of approximately $14 million related to fully executed renewal agreements for building leases that will go into effect starting in 2025.

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	12 Months Ended
	Dec. 31, 2024
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Schedule of Net Benefit Costs	NPPC for U.S. and international plans for 2024, 2023 and 2022 is as follows: U.S. Plans International Plans (In thousands) 2024 2023 2022 2024 2023 2022 Net Periodic Pension Cost (Income): Defined benefit pension plans: Service cost $ — $ — $ — $ 1,322 $ 1,245 $ 2,029 Interest cost 9,676 10,173 5,716 29,409 30,220 16,637 Expected return on plan assets (8,944) (7,000) (10,795) (33,049) (31,281) (39,179) Recognized prior service costs — — — 492 520 534 Recognized losses 4,179 4,601 4,732 15,060 14,316 13,060 Settlement/curtailment loss (gain) — — — (1,125) (42) (33) Defined benefit pension plan cost (income) 4,911 7,774 (347) 12,109 14,978 (6,952) Multiemployer pension plans 570 595 642 1,241 1,209 1,114 Defined contribution plans 9,985 8,468 7,082 5,690 5,396 5,111 Net periodic pension cost (income) $ 15,466 $ 16,837 $ 7,377 $ 19,040 $ 21,583 $ (727)
Schedule of Net Funded Status	The change in the financial status of the defined benefit pension plans and amounts recognized on the Consolidated Balance Sheets at December 31, 2024 and 2023 are as follows: U.S. Plans International Plans (In thousands) 2024 2023 2024 2023 Change in benefit obligation: Benefit obligation at beginning of year $ 209,177 $ 209,182 $ 642,648 $ 598,302 Service cost — — 1,322 1,245 Interest cost 9,676 10,173 29,409 30,220 Plan participants' contributions — — 12 13 Amendments — — — 74 Actuarial (gain) loss (17,591) 5,736 (57,451) 17,896 Settlements/curtailments — — (1,363) (203) Benefits paid (14,867) (15,914) (36,691) (36,705) Effect of foreign currency — — (15,803) 31,806 Benefit obligation at end of year $ 186,395 $ 209,177 $ 562,083 $ 642,648 Change in plan assets: Fair value of plan assets at beginning of year $ 180,927 $ 177,044 $ 669,021 $ 608,672 Actual return on plan assets 9,931 18,123 (20,357) 40,587 Employer contributions 7,301 1,674 14,778 24,715 Plan participants' contributions — — 12 13 Settlements/curtailments — — (192) (203) Benefits paid (14,867) (15,914) (36,691) (36,705) Effect of foreign currency — — (14,904) 31,942 Fair value of plan assets at end of year $ 183,292 $ 180,927 $ 611,667 $ 669,021 Funded status at end of year $ (3,103) $ (28,250) $ 49,584 $ 26,373
Schedule of Amounts Recognized in Balance Sheet	Amounts recognized on the Consolidated Balance Sheets for defined benefit pension plans consist of the following at December 31, 2024 and 2023: U.S. Plans International Plans December 31 December 31 (In thousands) 2024 2023 2024 2023 Noncurrent assets $ 9,917 $ — $ 63,879 $ 44,585 Current liabilities 1,713 1,832 507 726 Noncurrent liabilities 11,307 26,418 13,788 17,486 AOCI 72,260 95,016 332,026 358,631
Schedule of Net Periodic Benefit Cost Not yet Recognized	Amounts recognized in AOCI for defined benefit pension plans consist of the following at December 31, 2024 and 2023: U.S. Plans International Plans (In thousands) 2024 2023 2024 2023 Net actuarial loss $ 72,260 $ 95,016 $ 324,661 $ 350,469 Prior service cost — — 7,365 8,162 Total $ 72,260 $ 95,016 $ 332,026 $ 358,631
Schedule of Expected Benefit Payments	Expected benefit payments for defined benefit pension plans over the next ten years are as follows: (In millions) 2025 2026 2027 2028 2029 2030-2034 U.S. Plans $ 19.7 $ 15.6 $ 15.4 $ 15.2 $ 15.0 $ 71.5 International Plans 36.4 37.0 37.1 38.2 39.5 192.9
Schedule of Assumptions Used	The weighted-average actuarial assumptions used to determine the defined benefit pension plan NPPC for 2024, 2023 and 2022 were as follows: U.S. Plans International Plans Global Weighted-Average 2024 2023 2022 2024 2023 2022 2024 2023 2022 Discount rates 5.0 % 5.3 % 2.7 % 4.8 % 5.0 % 1.9 % 4.8 % 5.1 % 2.1 % Expected long-term rates of return on plan assets 7.0 % 7.0 % 6.3 % 5.3 % 5.1 % 4.4 % 5.7 % 5.5 % 4.7 % The weighted-average actuarial assumptions used to determine the defined benefit pension plan obligations at December 31, 2024 and 2023 were as follows: U.S. Plans International Plans Global Weighted-Average December 31 December 31 December 31 2024 2023 2024 2023 2024 2023 Discount rates 5.5 % 5.0 % 5.4 % 4.8 % 5.5 % 4.8 %
Schedule of Accumulated Benefit Obligations	The accumulated benefit obligation for all defined benefit pension plans at December 31, 2024 and 2023 was as follows: U.S. Plans International Plans December 31 December 31 (In millions) 2024 2023 2024 2023 Accumulated benefit obligation $ 186.4 $ 209.2 $ 558.4 $ 637.6
Schedule of Accumulated Benefit Obligations in Excess of Fair Value of Plan Assets	The projected benefit obligation, accumulated benefit obligation and fair value of plan assets for defined benefit pension plans with accumulated benefit obligations in excess of plan assets at December 31, 2024 and 2023 were as follows: U.S. Plans International Plans December 31 December 31 (In millions) 2024 2023 2024 2023 Projected benefit obligation $ 13.0 $ 209.2 $ 22.1 $ 27.8 Accumulated benefit obligation 13.0 209.2 19.9 24.1 Fair value of plan assets — 180.9 7.9 9.7
Schedule of Allocation of Plan Assets	The asset allocations attributable to the Company's international defined benefit pension plans at December 31, 2024 and 2023 and the long-term target allocation of plan assets, by asset category, are as follows: International Plans Asset Category Target Long-Term Percentage of Plan Assets 2024 2023 Equity securities 12.4 % 0.9 % 10.8 % Fixed income securities 82.8 % 95.0 % 83.3 % Cash and cash equivalents — 1.8 % 0.5 % Other (a) 4.8 % 2.3 % 5.4 %
U.S. Plans | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Schedule of Allocation of Plan Assets	At December 31, 2024 and 2023, the asset allocations attributable to the Company's U.S. defined benefit pension plans and the long-term target allocation of plan assets, by asset category, are as follows: Target Long-Term Percentage of Plan Assets U.S. Plans Asset Category 2024 2023 Domestic equity securities 4%-14% 8.8 % 10.7 % International equity securities 17%-27% 21.0 % 24.3 % Fixed income securities 61%-71% 65.4 % 52.8 % Cash and cash equivalents Less than 5% 0.9 % 0.9 % Other (a) 0%-8% 3.9 % 11.3 % (a) Investments within this caption include credit collection funds. The fair values of the Company's U.S. defined benefit pension plans' assets at December 31, 2024 by asset class are as follows: (In thousands) Total Level 1 Level 2 Investments Valued at Net Asset Value (a) Domestic equities: Common stocks $ 2,388 $ 2,388 $ — $ — Mutual funds—equities 13,748 13,748 — — International equities: Mutual funds—equities 38,398 38,398 — — Fixed income investments: U.S. Treasuries and collateralized securities 15,673 — 15,673 — Mutual funds—bonds 104,166 104,166 — — Cash and money market accounts 1,681 1,681 — — Other—partnerships/joint ventures 7,238 — — 7,238 Total $ 183,292 $ 160,381 $ 15,673 $ 7,238 The fair values of the Company's U.S. defined benefit pension plans' assets at December 31, 2023 by asset class are as follows: (In thousands) Total Level 1 Level 2 Investments Valued at Net Asset Value Domestic equities: Common stocks $ 2,791 $ 2,791 $ — $ — Mutual funds—equities 16,583 16,583 — — International equities: Mutual funds—equities 43,994 43,994 — — Fixed income investments: U.S. Treasuries and collateralized securities 13,920 — 13,920 — Mutual funds—bonds 81,634 81,634 — — Other—mutual funds 4,913 4,913 — — Cash and money market accounts 1,661 1,661 — — Other - partnerships/joint ventures 15,431 — — 15,431 Total $ 180,927 $ 151,576 $ 13,920 $ 15,431
International Plans | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Schedule of Allocation of Plan Assets	The fair values of the Company's international defined benefit pension plans' assets at December 31, 2024 by asset class are as follows: (In thousands) Total Level 1 Level 2 Equity securities: Mutual funds—equities $ 5,342 $ — $ 5,342 Fixed income investments: Mutual funds—bonds 576,540 — 576,540 Insurance contracts 4,394 — 4,394 Other: Other mutual funds 14,244 — 14,244 Cash and money market accounts 11,147 11,147 — Total $ 611,667 $ 11,147 $ 600,520 The fair values of the Company's international defined benefit pension plans' assets at December 31, 2023 by asset class are as follows: (In thousands) Total Level 1 Level 2 Equity securities: Mutual funds—equities $ 71,980 $ — $ 71,980 Fixed income investments: Mutual funds—bonds 552,898 — 552,898 Insurance contracts 4,631 — 4,631 Other: Other mutual funds 36,263 — 36,263 Cash and money market accounts 3,249 3,249 — Total $ 669,021 $ 3,249 $ 665,772

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2024
Income Tax Disclosure [Abstract]
Schedule of Income before Income Tax, Domestic and Foreign	Income (loss) from continuing operations before income taxes and equity income as reported on the Consolidated Statements of Operations consists of the following: (In thousands) 2024 2023 2022 U.S. $ (61,205) $ (19,598) $ (171,625) International (40,465) (33,072) 3,728 Total income (loss) from continuing operations before income taxes and equity income $ (101,670) $ (52,670) $ (167,897)
Schedule of Components of Income Tax Expense (Benefit)	Income tax expense (benefit) as reported on the Consolidated Statements of Operations consists of the following: (In thousands) 2024 2023 2022 Income tax expense (benefit): Currently payable: U.S. federal $ 897 $ (823) $ — U.S. state 2,701 3,591 975 International 24,884 23,801 16,428 Total income taxes currently payable 28,482 26,569 17,403 Deferred U.S. federal (5,667) 2,735 (12,655) Deferred U.S. state (2,997) (1,550) (1,935) Deferred international (2,752) 3,112 2,043 Total income tax expense (benefit) from continuing operations $ 17,066 $ 30,866 $ 4,856
Schedule of Effective Income Tax Rate Reconciliation	A reconciliation of the normal expected statutory U.S. federal income tax expense (benefit) to the actual Income tax expense (benefit) from continuing operations as reported on the Consolidated Statements of Operations is as follows: (In thousands) 2024 2023 2022 U.S. federal income tax expense (benefit), at statutory tax rate of 21% $ (21,350) $ (11,060) $ (35,259) U.S. state income taxes, net of federal income tax benefit (1,296) 624 (644) U.S. other domestic deductions and credits (1,084) (1,275) (1,216) Difference in effective tax rates on international earnings and remittances 29,019 26,372 11,166 Uncertain tax position contingencies and settlements (51) (768) (290) Changes in realization of deferred tax assets 10,366 14,498 8,262 U.S. non-deductible expenses 3,663 278 24 Nondeductible goodwill charges 3,676 — 19,548 PP&E / Intangible asset impairment — 2,961 3,150 State deferred tax rate changes (63) 304 343 Foreign derived intangible income deduction (1,675) (2,199) (1,792) Share-based compensation 1,967 1,131 1,564 Capital loss (6,106) — — Total income tax expense (benefit) from continuing operations $ 17,066 $ 30,866 $ 4,856
Schedule of Deferred Tax Assets and Liabilities	The income tax effects of the temporary differences giving rise to the Company's deferred tax assets and liabilities at December 31, 2024 and 2023 are as follows: 2024 (a) 2023 (a) (In thousands) Asset Liability Asset Liability Depreciation and amortization $ — $ 47,816 $ — $ 53,577 Right-of-use assets — 22,851 — 25,417 Operating lease liabilities 23,302 — 25,752 — Expense accruals 26,428 — 33,810 — Inventories 2,324 — 3,779 — Provision for receivables 2,345 — 3,801 — Deferred revenue 11,582 — 6,513 — Operating loss carryforwards 128,412 — 118,309 — Tax credit carryforwards 13,480 — 15,298 — Pensions — 11,916 — 599 Currency adjustments 98 — — 1,171 Section 163(j) disallowed interest expense 40,054 — 25,937 — Research and development 8,236 — 6,013 — Stock based compensation 7,968 — 7,387 — Other 1,881 — — 812 Subtotal 266,110 82,583 246,599 81,576 Valuation allowance (192,745) — (177,888) — Total deferred income taxes $ 73,365 $ 82,583 $ 68,711 $ 81,576 (a) Does not include approximately $1.1 billion of statutory loss carryforwards within Luxembourg for which the Company considers the utilization of these attributes remote and as such no deferred tax asset or corresponding valuation allowance has been recorded.
Tax Years Subjected to Examniation	The tax years that remain subject to examination for the Company's major tax jurisdictions as of December 31, 2024 are shown below: Jurisdiction Earliest Open Year Brazil 2020 China 2019 France 2022 United States: Federal income tax 2021 State income tax 2018
Schedule of Unrecognized Tax Benefits Roll Forward	A reconciliation of the change in the unrecognized income tax benefits balance from January 1, 2022 to December 31, 2024 is as follows: (In thousands) Unrecognized Deferred Unrecognized Balances, January 1, 2022 $ 3,127 $ (22) $ 3,105 Additions for tax positions related to the current year (includes currency translation adjustment) 189 (1) 188 Statutes of limitation expirations (524) 2 (522) Balance at December 31, 2022 2,792 (21) 2,771 Additions for tax positions related to the current year (includes currency translation adjustment) 439 (1) 438 Statutes of limitation expirations (1,106) 5 (1,101) Balance at December 31, 2023 2,125 (17) 2,108 Additions for tax positions related to the current year (includes currency translation adjustment) 228 9 237 Statutes of limitation expirations (577) — (577) Total unrecognized income tax benefits that, if recognized, would impact the effective income tax rate at December 31, 2024 $ 1,776 $ (8) $ 1,768

Commitment and Contingencies (T

Commitment and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2024
Commitments and Contingencies Disclosure [Abstract]
Schedule of Loss Contingencies by Contingency	The following table summarizes information related to the location and undiscounted amount of the Company's environmental liabilities: (In thousands) December 31 December 31 Current portion of environmental liabilities (a) $ 11,815 $ 7,540 Long-term environmental liabilities 46,585 25,682 Total environmental liabilities (b) $ 58,400 $ 33,222 (a) The current portion of environmental liabilities is included in the caption Other current liabilities on the Consolidated Balance Sheets. (b) The increase in Total environmental liabilities at December 31, 2024 from the prior year is primarily from the salt cakes reserve discussed below regarding the Company's operations in Bahrain.

Capital Stock (Tables)

Capital Stock (Tables)	12 Months Ended
	Dec. 31, 2024
Equity [Abstract]
Schedule of Common Stock Outstanding Roll Forward	The following table summarizes the Company's common stock activity for each period during the twelve months ended 2022, 2023 and 2024: Shares Treasury Shares Outstanding As of January 1, 2022 115,906,393 36,690,847 79,215,546 Shares issued for vested restricted stock units 341,051 131,089 209,962 Shares issued for vested restricted stock awards 87,765 40,304 47,461 Stock appreciation rights exercised 23,311 6,640 16,671 As of December 31, 2022 116,358,520 36,868,880 79,489,640 Shares issued for vested restricted stock units 401,385 122,659 278,726 Shares issued for vested restricted stock awards 124,106 57,637 66,469 As of December 31, 2023 116,884,011 37,049,176 79,834,835 Shares issued for vested restricted stock units 590,133 227,794 362,339 Stock appreciation rights exercised 844 241 603 As of December 31, 2024 117,474,988 37,277,211 80,197,777
Schedule of Earnings Per Share, Basic and Diluted	The following is a reconciliation of the average shares of common stock used to compute basic earnings per common share to the shares used to compute diluted earnings per common share as shown on the Consolidated Statements of Operations: (In thousands, except per share data) 2024 2023 2022 Income (loss) from continuing operations attributable to Enviri Corporation common stockholders $ (124,058) $ (82,320) $ (176,569) Weighted-average shares outstanding—basic 80,118 79,796 79,493 Dilutive effect of stock-based compensation — — — Weighted-average shares outstanding—diluted 80,118 79,796 79,493 Income (loss) from continuing operations per common share, attributable to Enviri Corporation common stockholders: Basic $ (1.55) $ (1.03) $ (2.22) Diluted $ (1.55) $ (1.03) $ (2.22)
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 or the market conditions for the performance share units were not met: (In thousands) 2024 2023 2022 Restricted stock units 1,476 1,219 672 Stock appreciation rights 2,618 2,303 2,092 Performance share units 1,797 1,341 1,040

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2024
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Schedule of restricted stock units issued and compensation expense	The following table summarizes RSUs issued and the compensation expense recorded for the years ended December 31, 2024, 2023, and 2022: RSUs (a) Weighted Average Fair Value Expense (Dollars in thousands, except per unit) 2024 2023 2022 Directors: 2021 23,224 21.53 — — 167 2022 63,696 7.85 — 167 333 2023 80,705 9.03 213 516 — 2024 80,125 7.80 406 — — Employees: 2019 270,864 22.25 — — 320 2020 522,087 8.22 — 90 800 2021 343,125 18.62 157 946 1,355 2022 450,915 12.36 1,035 1,095 1,547 2023 926,010 7.09 1,962 1,722 — 2024 825,499 8.22 2,565 — — Total $ 6,338 $ 4,536 $ 4,522 (a) Represents number of awards originally issued.
Schedule of restricted stock unit activity	RSU activity for the year ended December 31, 2024 was as follows: Number of Shares Weighted Average Non-vested at December 31, 2023 1,219,321 $ 8.63 Granted 905,624 8.19 Vested (591,442) 9.46 Forfeited (57,847) 8.55 Non-vested at December 31, 2024 1,475,656 $ 8.01
Schedule of Stock Appreciation Rights award activity	SARs activity for the year ended December 31, 2024 was as follows: Number of Shares Weighted Average Exercise Price Aggregate Intrinsic Value (in millions) (b) Outstanding, December 31, 2023 2,303,018 $ 13.01 $ 1.30 Granted 567,967 8.20 Exercised (6,563) 7.45 Forfeited/Expired (246,204) 21.31 Outstanding, December 31, 2024 2,618,218 $ 11.20 $ 0.40
Schedule of nonvested awards activity	The following table summarizes information related to outstanding and exercisable SARs at December 31, 2024: SARs Outstanding SARs Exercisable Range of Exercisable Prices Vested Non-vested Weighted-Average Exercise Price per Share Weighted-Average Remaining Contractual Life in Years Number Exercisable Weighted-Average Exercise Price per Share $5.02 - $13.70 1,103,357 928,964 $ 9.07 6.30 1,103,357 $ 9.69 $16.53 - $22.51 585,897 — 18.58 2.65 585,897 18.58 1,689,254 928,964 $ 11.20 5.48 1,689,254 $ 12.77
Stock Appreciation Rights (SARs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Schedule of stock appreciation rights valuation assumptions	The table below summarizes the total SARs granted and the fair value of each grant estimated on the grant date using a Black-Scholes pricing model with the following assumptions: Number of Shares Granted Risk-free Interest Rate Dividend Yield Expected Life (Years) Volatility SAR Grant Price Fair Value of SAR March 2022 Grant 312,987 1.67 % — % 6.0 60.3 % $ 12.65 $ 7.20 September 2022 Grant 10,000 3.56 % — % 6.0 60.6 % $ 5.02 $ 2.97 October 2022 Grant 10,000 4.10 % — % 6.0 61.3 % $ 5.26 $ 3.17 December 2022 Grant 10,000 3.75 % — % 6.0 62.4 % $ 6.15 $ 3.72 March 2023 Grant 404,594 4.20 % — % 6.0 62.6 % $ 7.45 $ 4.56 May 2023 Grant 48,427 3.48 % — % 6.0 63.0 % $ 9.31 $ 5.64 March 2024 Grant 567,967 4.04 % — % 6.0 63.4 % $ 8.20 $ 5.04
Schedule of weighted-average grant-date fair value of unvested options	Weighted-average grant date fair value of non-vested SARs for the year ended December 31, 2024 was as follows: Number of Shares Weighted-Average Grant Date Fair Value Non-vested shares, December 31, 2023 598,304 $ 5.51 Granted 567,967 8.20 Vested (220,327) 6.17 Forfeited (16,980) 5.16 Non-vested shares, December 31, 2024 928,964 $ 5.07
Performance Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Schedule of stock appreciation rights valuation assumptions	Under the 2013 Plan, the Company granted the following shares presented in the table below and estimated the fair value of these grants on the grant date using a Monte Carlo pricing model with the following assumptions: PSUs Issued Number of Shares Granted Risk-free Interest rate Dividend Yield Expected Life (Years) Volatility Fair Value per PSU March 2022 Grant 500,624 1.59 % — % 2.83 50.4 % $ 16.54 March 2023 Grant 758,965 4.67 % — % 2.82 43.9 % $ 10.91 May 2023 Grant 29,337 3.75 % — % 2.65 41.5 % $ 15.24 March 2024 Grant 778,702 4.26 % — % 2.81 39.8 % $ 12.04
Schedule of weighted-average grant-date fair value of unvested options	A summary of the Company's non-vested PSU activity during the year ending December 31, 2024 was as follows: Number of Shares Weighted-Average Grant Date Fair Value Non-vested shares, December 31, 2023 1,108,256 $ 12.87 Granted 767,699 12.04 Vested, not issued (a) (339,496) 16.54 Forfeited (79,071) 12.80 Non-vested shares, December 31, 2024 1,457,388 $ 11.58 (a) The measurement period for PSUs issued in 2022 ended on December 31, 2024 and these shares vested but will not be issued until the Board certifies the measurement period results in early 2025. A total of 0 shares are expected to be issued.

Financial Instruments (Tables)

Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2024
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Fair value of outstanding derivative contracts recorded as assets and liabilities	The fair value of outstanding derivative contracts recorded as assets and liabilities on the Company's 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 December 31, 2024 Asset derivatives (Level 2): Foreign currency exchange forward contracts Other current assets $ 347 $ 7,590 $ 7,937 Interest rate swaps Other assets 5,250 — 5,250 Total $ 5,597 $ 7,590 $ 13,187 Liability derivatives (Level 2): Foreign currency exchange forward contracts Other current liabilities $ 80 $ 987 $ 1,067 Interest rate swaps Other current liabilities 217 — 217 Total $ 297 $ 987 $ 1,284 December 31, 2023 Asset derivatives (Level 2): Foreign currency exchange forward contracts Other current assets $ 77 $ 1,597 $ 1,674 Interest rate swaps Other current assets 1,443 — 1,443 Total $ 1,520 $ 1,597 $ 3,117 Liability derivatives (Level 2): Foreign currency exchange forward contracts Other current liabilities $ 561 $ 8,064 $ 8,625 Interest rate swaps Other liabilities 2,150 — 2,150 Total $ 2,711 $ 8,064 $ 10,775
Derivative Instruments, Gain (Loss) [Table Text Block]	The effect of derivative instruments on the Company's Consolidated Statements of Operations and the Consolidated Statements of Comprehensive Income (Loss) was as follows: Derivatives Designated as Hedging Instruments Gain (Loss) Recognized in OCI on Derivatives Loss (Gain) Reclassified from AOCI into Income - Effective Portion or Equity (In thousands) 2024 2023 2022 2024 2023 2022 Foreign currency exchange forward contracts $ 592 $ (1,696) $ 1,966 $ (695) $ 1,638 $ (1,746) Interest rate swaps 8,757 1,869 — (3,018) (2,576) 4,245 $ 9,349 $ 173 $ 1,966 $ (3,713) $ (938) $ 2,499
Schedule of Cash Flow Hedging Instruments, Statements of Financial Performance and Financial Position, Location [Table Text Block]	The locations and amounts of gain (loss) recognized on the Consolidated Statements of Operations are as follows: 2024 (in thousands) Product Revenues Interest Expense Total amounts in the Consolidated Statements of Operations in which the effects of cash flow hedges are recorded $ 372,452 $ (112,217) Interest rate swaps: Gain or (loss) reclassified from AOCI into income — 3,018 Foreign exchange contracts: Gain or (loss) reclassified from AOCI into income 695 — 2023 (in thousands) Product Revenues Interest Expense Total amounts in the Consolidated Statements of Operations in which the effects of cash flow hedges are recorded $ 434,308 $ (107,081) Interest rate swaps: Gain or (loss) reclassified from AOCI into income — 2,576 Foreign exchange contracts: Gain or (loss) reclassified from AOCI into income (1,638) — 2022 Product Revenues Interest Expense Total amounts in the Consolidated Statements of Operations in which the effects of cash flow hedges are recorded $ 376,398 $ (76,807) Interest rate swaps: Gain or (loss) reclassified from AOCI into income — (4,245) Amount recognized in earnings due to ineffectiveness — 1,862 Foreign exchange contracts: Gain or (loss) reclassified from AOCI into income 1,746 —
Derivatives Not Designated as Hedging Instruments	Derivatives Not Designated as Hedging Instruments Location of Gain (Loss) Recognized in Income on Derivatives Amount of Gain (Loss) Recognized in Income on Derivatives for the Twelve Months Ended December 31 (a) (In thousands) 2024 2023 2022 Foreign currency exchange forward contracts Cost of services and products sold $ 25,184 $ 426 $ 19,808 (a) These gains (losses) offset amounts recognized in cost of sales sold principally as a result of intercompany or third-party foreign currency exposures.

Information by Segment and Ge_2

Information by Segment and Geographic Area (Tables)	12 Months Ended
	Dec. 31, 2024
Segment Reporting [Abstract]
Schedule of Revenue from External Customers and Long-Lived Assets, by Geographical Areas	Countries with revenues from unaffiliated customers or net PP&E of 10% or more of the consolidated totals for at least one of the periods presented below are as follows: Revenues from Unaffiliated Customers Years ended December 31 (In thousands) 2024 2023 2022 By geographic location (a) : U.S. $ 1,340,795 $ 1,406,262 $ 1,239,345 International 1,001,850 959,758 894,636 Total revenues from unaffiliated customers $ 2,342,645 $ 2,366,020 $ 2,133,981 (a) Revenues are attributed to individual countries based on the location of the facility generating the revenue.
Schedule of Disclosure on Geographic Areas, Long-Lived Assets in Individual Foreign Countries by Country [Table Text Block]	Property, Plant and Equipment, Net December 31 (In thousands) 2024 2023 By geographic location: U.S. $ 338,679 $ 339,231 International 325,613 368,166 Total property, plant and equipment, net $ 664,292 $ 707,397
Schedule of Segment Operating Information by Segment	Operating Information by Segment The accounting policies for the three reportable segments are consistently applied, as described in Note 1, Summary of Significant Accounting Policies. The Company's chief operating decision maker (the "CODM") is the Company's Chairman and Chief Executive Officer. The CODM uses segment operating income/(loss) as the profit measure to evaluate segment performance and allocate resources across segments. Corporate unallocated expenses, interest income, interest expense, facility fees and debt-related income (expense) and defined benefit pension income (expense) are centrally managed costs and are, therefore, excluded from this profit measure to provide better understanding of the Company's segment operating results. The CODM considers variances of actual performance to the Company's annual operating plan and periodic forecasts when making decisions. The following tables include information about the Company's revenues and operating income (loss) by reporting segment, along with significant segment expenses and other segment information, for the years ended December 31, 2024, 2023 and 2022: Year Ended December 31, 2024 (in thousands) Harsco Clean Earth Harsco Rail Total Segment Corporate Total Segment Profit and Loss: Total revenues 1,111,512 939,845 291,288 $ 2,342,645 — $ 2,342,645 Less: Cost of services and products sold (a) 948,591 690,160 270,330 1,909,081 — 1,909,081 Selling, general and administrative expenses 113,845 156,378 48,461 318,684 40,704 359,388 Goodwill and other intangible asset impairment charges 2,840 — 13,026 15,866 — 15,866 Property, plant and equipment impairment charge 23,444 — — 23,444 — 23,444 Remeasurement of long-lived assets — — 10,695 10,695 — 10,695 Gain on sale of businesses, net (10,029) — — (10,029) (449) (10,478) Other segment activities (a)(b) 808 1,151 6,808 8,767 (5,863) 2,904 Operating income (loss) from continuing operations 32,013 92,156 (58,032) $ 66,137 (34,392) $ 31,745 Plus: Interest income 6,795 Interest expense (112,217) Facility fees and debt-related income (expense) (11,265) Defined benefit pension income (expense) (16,728) Income (loss) from continuing operations before income taxes and equity income $ (101,670) Other Segment Information: Depreciation 109,756 33,840 3,478 $ 147,074 1,255 $ 148,329 Amortization (c) 3,068 23,976 224 $ 27,268 4,203 $ 31,471 Capital expenditures 98,845 32,754 4,756 $ 136,355 236 $ 136,591 Total assets 1,263,031 993,598 350,157 $ 2,606,786 43,447 $ 2,650,233 Year Ended December 31, 2023 (in thousands) Harsco Clean Harsco Total Segment Corporate Total Segment Profit and Loss: Total revenues 1,140,904 928,321 296,795 $ 2,366,020 — $ 2,366,020 Less: Cost of services and products sold (a) 942,219 694,756 277,812 1,914,787 — 1,914,787 Selling, general and administrative expenses 109,131 154,513 45,770 309,414 44,571 353,985 Property, plant and equipment impairment charge 14,099 — — 14,099 — 14,099 Other segment activities (a)(b) (2,180) 2,078 4,884 4,782 (1,571) 3,211 Operating income (loss) from continuing operations 77,635 76,974 (31,671) $ 122,938 (43,000) $ 79,938 Plus: Interest income 6,809 Interest expense (107,081) Facility fees and debt-related income (expense) (10,762) Defined benefit pension income (expense) (21,574) Income (loss) from continuing operations before income taxes and equity income $ (52,670) Other Segment Information: Depreciation 113,571 23,252 — $ 136,823 2,133 $ 138,956 Amortization (c) 4,030 24,583 — $ 28,613 3,795 $ 32,408 Capital expenditures 104,045 32,100 2,453 $ 138,598 427 $ 139,025 Total assets 1,417,278 981,723 369,022 $ 2,768,023 86,675 $ 2,854,698 Year Ended December 31, 2022 (in thousands) Harsco Clean Harsco Total Segment Corporate Total Segment Profit and Loss: Total revenues 1,061,239 827,826 244,916 $ 2,133,981 — $ 2,133,981 Less: Cost of services and products sold (a) 881,249 675,283 242,951 1,799,483 — 1,799,483 Selling, general and administrative expenses 99,855 129,401 40,967 270,223 34,642 304,865 Goodwill and other intangible asset impairment charges 15,000 104,580 — 119,580 — 119,580 Other segment activities (a)(b) 5,576 347 4,679 10,602 347 10,949 Operating income (loss) from continuing operations 59,559 (81,785) (43,681) $ (65,907) (34,989) $ (100,896) Plus: Interest income 3,829 Interest expense (76,807) Facility fees and debt-related income (expense) (2,956) Defined benefit pension income (expense) 8,933 Income (loss) from continuing operations before income taxes and equity income $ (167,897) Other Segment Information: Depreciation 108,880 18,836 — $ 127,716 1,996 $ 129,712 Amortization (c) 6,809 24,299 — $ 31,108 3,029 $ 34,137 Capital expenditures 109,508 21,996 1,618 $ 133,122 4,038 $ 137,160 (a) Cost of services and products sold is a significant expense category provided to the CODM at the segment-level. (b) Other segment activities include amounts reflected in the captions, Research and development costs, Cost of services and products sold and Other (income) expenses, net, on the Company's Consolidated Statements of Operations.

Revenue Recognition (Tables)

Revenue Recognition (Tables)	12 Months Ended
	Dec. 31, 2024
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 for the years ended December 31, 2024, 2023 and 2022 is as follows: Year Ended December 31, 2024 (In thousands) Harsco Clean Earth Segment Harsco Rail Segment Consolidated Totals Primary Geographical Markets (a) : North America $ 292,274 $ 939,845 $ 173,424 $ 1,405,543 Western Europe 425,775 — 84,398 510,173 Latin America (b) 154,684 — 5,578 160,262 Asia-Pacific 117,523 — 27,888 145,411 Middle East and Africa 103,957 — — 103,957 Eastern Europe 17,299 — — 17,299 Total Revenues $ 1,111,512 $ 939,845 $ 291,288 $ 2,342,645 Key Product and Service Groups: Environmental services related to resource recovery for metals manufacturing; and related logistical services $ 967,188 $ — $ — $ 967,188 Ecoproducts 120,896 — — 120,896 Environmental systems for aluminum dross and scrap processing 23,428 — — 23,428 Railway track maintenance equipment — — 113,039 113,039 After market parts and services; safety and diagnostic technology — — 117,327 117,327 Railway contracting services — — 60,922 60,922 Hazardous waste processing solutions — 778,402 — 778,402 Soil and dredged materials processing and reuse solutions — 161,443 — 161,443 Total Revenues $ 1,111,512 $ 939,845 $ 291,288 $ 2,342,645 Year Ended December 31, 2023 (In thousands) Harsco Environmental Segment Clean Earth Segment Harsco Rail Segment Consolidated Totals Primary Geographical Markets (a) : North America $ 318,574 $ 928,321 $ 214,893 $ 1,461,788 Western Europe 431,893 — 57,301 489,194 Latin America (b) 170,194 — 2,540 172,734 Asia-Pacific 113,800 — 22,061 135,861 Middle East and Africa 86,867 — — 86,867 Eastern Europe 19,576 — — 19,576 Total Revenues $ 1,140,904 $ 928,321 $ 296,795 $ 2,366,020 Key Product and Service Groups: Environmental services related to resource recovery for metals manufacturing; and related logistical services $ 950,961 $ — $ — $ 950,961 Ecoproducts 162,291 — — 162,291 Environmental systems for aluminum dross and scrap processing 27,652 — — 27,652 Railway track maintenance equipment — — 128,155 128,155 After market parts and services; safety and diagnostic technology — — 121,039 121,039 Railway contracting services — — 47,601 47,601 Hazardous waste processing solutions — 767,338 — 767,338 Soil and dredged materials processing and reuse solutions — 160,983 — 160,983 Total Revenues $ 1,140,904 $ 928,321 $ 296,795 $ 2,366,020 Year Ended December 31, 2022 (In thousands) Harsco Environmental Segment Clean Earth Segment Harsco Rail Segment Consolidated Totals Primary Geographical Markets (a) : North America $ 297,544 $ 827,826 $ 163,998 $ 1,289,368 Western Europe 389,713 — 45,507 435,220 Latin America (b) 155,235 — 1,556 156,791 Asia-Pacific 119,433 — 33,855 153,288 Middle East and Africa 79,562 — — 79,562 Eastern Europe 19,752 — — 19,752 Total Revenues $ 1,061,239 $ 827,826 $ 244,916 $ 2,133,981 Key Product and Service Groups: Environmental services related to resource recovery for metals manufacturing; and related logistical services $ 900,426 $ — $ — $ 900,426 Ecoproducts 145,911 — — 145,911 Environmental systems for aluminum dross and scrap processing 14,902 — — 14,902 Railway track maintenance equipment — — 100,032 100,032 After market parts and services; safety and diagnostic technology — — 118,829 118,829 Railway contracting services — — 26,055 26,055 Hazardous waste processing solutions — 681,804 — 681,804 Soil and dredged materials processing and reuse solutions — 146,022 — 146,022 Total Revenues $ 1,061,239 $ 827,826 $ 244,916 $ 2,133,981 (a) Revenues are attributed to individual countries based on the location of the facility generating the revenue. (b) Includes Mexico.
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction	The table below represents the expected fulfillment year of Company's fixed, unsatisfied performance obligations, where the expected contract duration exceeds one year, by segment, and exclude any variable fees, fixed fees subject to indexation and any performance obligations expected to be satisfied within one year: (In thousands) Harsco Harsco Rail Segment 2025 $ 17,019 $ 51,037 2026 15,367 24,980 2027 12,803 17,955 2028 11,121 5,137 2029 3,132 4,038 Thereafter 3,132 2,676 Total remaining performance obligations $ 62,574 $ 105,823

Other Expenses (Tables)

Other Expenses (Tables)	12 Months Ended
	Dec. 31, 2024
Other Income and Expenses [Abstract]
Schedule of other expenses (income)	The major components of this Consolidated Statements of Operations caption, broken out by operating segment, are as follows: (In thousands) 2024 2023 2022 Net gains Harsco Environmental Segment $ (3,357) $ (250) $ (1,869) Clean Earth Segment — — (1,512) Harsco Rail Segment — (2,311) — Corporate (3,272) — (632) Total net gains (6,629) (2,561) (4,013) Employee termination benefit costs Harsco Environmental Segment 6,013 1,977 4,998 Clean Earth Segment 521 1,399 1,786 Harsco Rail Segment 640 (645) 1,725 Corporate 1,179 275 (294) Total employee termination benefit costs 8,353 3,006 8,215 Other costs (income) to exit activities Harsco Environmental Segment (3,615) (7,810) 39 Clean Earth Segment — — — Harsco Rail Segment 9 3,576 4,003 Corporate 2,060 2,669 1,407 Total other costs (income) to exit activities (1,546) (1,565) 5,449 Asset impairments Harsco Environmental Segment 2,771 88 582 Clean Earth Segment 567 — 59 Harsco Rail Segment 1,921 — 95 Total asset impairments 5,259 88 736 Contingent consideration adjustments Clean Earth Segment — — (827) Corporate — (848) — Total contingent consideration adjustments — (848) (827) Other (income) expense — 289 2,094 Total other (income) expenses, net $ 5,437 $ (1,591) $ 11,654

Components of Accumulated Oth_2

Components of Accumulated Other Comprehensive Loss (Tables)	12 Months Ended
	Dec. 31, 2024
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Components of accumulated other comprehensive loss	The components of AOCI, net of the effect of income taxes, and activity for the years ended December 31, 2024 and 2023 are as follows: Components of AOCI - 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, 2022 $ (213,104) $ 157 $ (354,699) $ 10 $ (567,636) OCI before reclassifications 29,495 (a) 64 (b) (19,266) (c) 5 10,298 Amounts reclassified from AOCI, net of tax (507) (691) 18,225 — 17,027 Total OCI 28,988 (627) (1,041) 5 27,325 Less: OCI attributable to noncontrolling interests 617 — — — 617 OCI attributable to Enviri Corporation 29,605 (627) (1,041) 5 27,942 Balance at December 31, 2023 (183,499) (470) (355,740) 15 (539,694) OCI before reclassifications (46,316) (a) 7,036 (b) 24,133 (c) 7 (15,140) Amounts reclassified from AOCI, net of tax (108) (2,797) 17,550 — 14,645 Total OCI (46,424) 4,239 41,683 7 $ (495) Less: OCI attributable to noncontrolling interests 1,225 — — — 1,225 OCI attributable to Enviri Corporation (45,199) 4,239 41,683 7 730 Balance at December 31, 2024 $ (228,698) $ 3,769 $ (314,057) $ 22 $ (538,964) (a) Principally foreign currency fluctuation. (b) Principally net change from periodic revaluations. (c) Principally changes due to annual actuarial remeasurements and foreign currency translation.
Amounts reclassified out of accumulated other comprehensive loss	Amounts reclassified from AOCI for 2024 and 2023 are as follows: Year Ended December 31, 2024 Year Ended December 31, 2023 Affected Caption on the (In thousands) Amortization of defined benefit pension items (d) : Actuarial losses $ 19,239 $ 18,917 Defined benefit pension income (expense) Prior-service costs 492 520 Defined benefit pension income (expense) Settlement/curtailment gain (1,125) (42) Defined benefit pension income (expense) Total before tax 18,606 19,395 Tax benefit (1,056) (1,170) Total reclassification of defined benefit pension items, net of tax $ 17,550 $ 18,225 Amortization of cash flow hedging instruments (e) : Foreign currency exchange forward contracts $ (695) $ 1,638 Product revenues Interest rate swaps (3,018) (2,576) Interest expense Total before tax (3,713) (938) Tax benefit 916 247 Total reclassification of cash flow hedging instruments $ (2,797) $ (691) Recognition of cumulative foreign exchange translation adjustments: Gain on substantial liquidation of subsidiaries (f) $ (108) $ (507) Other (income) expenses, net Total reclassification of cumulative foreign exchange translation adjustments $ (108) $ (507) (d) These AOCI components are included in the computation of NPPC. See Note 10, Employee Benefit Plans, for additional information. (e) See Note 15, Financial Instruments for additional information.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Accounting Policies [Abstract]
Restricted cash	$ 1,799	$ 3,375
Revenue Recognition, Costs-to-Cost Method, Revenue Recognized	$ 48,500	$ 70,900	$ 49,600

Summary of Significant Accoun_4

Summary of Significant Accounting Policies (Details 2) - Self-insurance - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Loss Contingencies [Line Items]
Decrease in pre-tax insurance expense due to retrospective insurance reserve adjustments from continuing operations	$ (1.1)	$ 1.6	$ (1.6)
Liabilities for asserted and unasserted claims	30.3	32.5
Liabilities covered by insurance carriers	$ 5.9	$ 6.5

Summary of Significant Accoun_5

Summary of Significant Accounting Policies (Details 3) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Derivative [Line Items]
Total revenues	$ 2,342,645	$ 2,366,020	$ 2,133,981
Foreign currency exchange forward contracts | Maximum
Derivative [Line Items]
Maximum typical term of foreign currency forward exchange contracts (in days)	90 days

Acquisitions and Dispositions -

Acquisitions and Dispositions - Schedule of Balance Sheet from Disposal of Harsco Rail Segment (Details) (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Prepaid Expense	$ 62,435	$ 58,723
Other current assets	14,880	11,023
Income taxes payable	$ 5,747	7,567
Revision of Prior Period, Adjustment | Harsco Rail
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Prepaid Expense		28,797
Other current assets		2,895
Income taxes payable		1,434
Discontinued Operations, Held-for-sale | Harsco Rail
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Trade accounts receivable, net		57,415
Other receivables		6,708
Inventories		103,077
Current portion of contract assets		56,341
Property, plant and equipment, net		44,113
Right-of-use assets, net		7,050
Goodwill		13,026
Intangible assets, net		3,122
Disposal Group, Including Discontinued Operation, Defined Benefit Plan Assets, Noncurrent		344
Deferred income tax assets		973
Other assets		22,448
Total assets		346,309
Accounts payable		44,703
Accrued compensation		6,056
Current portion of operating lease liabilities		3,656
Other current liabilities		32,912
Reserve for contracts		52,725
Current portion of advances on contracts		30,550
Operating lease liabilities		3,331
Deferred tax liabilities		350
Other liabilities		494
Total liabilities		$ 176,211

Acquisitions and Dispositions_2

Acquisitions and Dispositions - Schedule of Income (Loss) from Discontinued Operations Harsco Rail (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total revenues			$ 2,342,645	$ 2,366,020	$ 2,133,981
Cost of services and products sold					1,799,483
Selling, general and administrative costs			359,388	353,985	304,865
Research and development expenses			3,961	3,458	2,858
Other Operating Income (Expense), Net			(5,437)	1,591	(11,654)
Total costs and expenses			2,310,900	2,286,082	2,234,877
Operating income from continuing operations			31,745	79,938	(100,896)
Interest income			6,795	6,809	3,829
Interest Expense, Operating and Nonoperating			112,217	107,081	76,807
Defined benefit pension income (expense)			16,728	21,574	(8,933)
Income from continuing operations before income taxes			(101,670)	(52,670)	(167,897)
Income Tax Expense (Benefit)			17,066	30,866	4,856
Income from continuing operations			(118,746)	(84,297)	(172,931)
Revision of Prior Period, Adjustment
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cost of services and products sold	$ 282,469		242,584
Revision of Prior Period, Adjustment | Harsco Rail
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total revenues	296,795			244,916
Selling, general and administrative costs	41,602			36,799
Research and development expenses	2,172			2,168
Other Operating Income (Expense), Net	1,628			6,917
Total costs and expenses	327,871			288,468
Operating income from continuing operations	(31,076)			(43,552)
Interest income	139			270
Interest Expense, Operating and Nonoperating	(3,209)			(1,651)
Defined benefit pension income (expense)	26			(5)
Income from continuing operations before income taxes	(34,120)			(44,938)
Income Tax Expense (Benefit)	(2,681)			5,525
Income from continuing operations	$ (36,801)			(39,413)
Services
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total revenues			1,970,193	1,931,712	1,757,583
Cost of services and products sold			1,557,473	1,511,689	1,438,421
Services | Revision of Prior Period, Adjustment | Harsco Rail
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total revenues		$ 52,430		29,331
Cost of services and products sold		34,552		19,550
Product
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total revenues			372,452	434,308	376,398
Cost of services and products sold			$ 345,114	404,442	$ 357,499
Product | Revision of Prior Period, Adjustment | Harsco Rail
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total revenues		244,365		215,585
Cost of services and products sold		$ 247,917		$ 223,034

Acquisitions and Dispositions_3

Acquisitions and Dispositions - Narrative (Details) - USD ($) $ in Thousands			3 Months Ended	12 Months Ended
	Aug. 29, 2024	Apr. 01, 2024	Dec. 31, 2024	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Sep. 30, 2024
Business Acquisition [Line Items]
Contract estimated forward loss provision for Harsco Rail Segment				$ 32,700	$ 32,800	$ 44,500
Gain (Loss) on Disposition of Business				10,478	0	$ 0
Revolving Credit Facility | Line of Credit [Member]
Business Acquisition [Line Items]
Unamortized Debt Issuance Expense			$ 4,400	$ 4,400
Harsco Rail
Business Acquisition [Line Items]
Increase (Decrease) in Carrying Amount of Assets							$ 10,700
SBB
Business Acquisition [Line Items]
Percentage Complete			91%	91%
Contract estimated forward loss provision for Harsco Rail Segment					7,300
Network Rail
Business Acquisition [Line Items]
Contract estimated forward loss provision for Harsco Rail Segment			$ 2,800	$ 16,100	14,400
Network Rail | Contract 2
Business Acquisition [Line Items]
Percentage Complete			64%	64%
Deutsche Bahn
Business Acquisition [Line Items]
Percentage Complete			48%	48%
Contract estimated forward loss provision for Harsco Rail Segment			$ 7,200	$ 14,400	39,900
Harsco Rail | Discontinued Operations, Held-for-sale
Business Acquisition [Line Items]
Goodwill					13,026
Accounts payable					$ 44,703
Performix Metallurgical Additives, LLC | Disposal Group, Disposed of by Sale, Not Discontinued Operations
Business Acquisition [Line Items]
Gain (Loss) on Disposition of Business		$ 1,800
Gain (Loss) On Disposition Of Business, Net Of Tax		1,300
Disposal Group, Including Discontinued Operation, Accounts, Notes and Loans Receivable, Net	$ 4,700
Goodwill	5,300
Proceeds from Divestiture of Businesses, Gross		$ 17,500
Reed Minerals, LLC | Disposal Group, Disposed of by Sale, Not Discontinued Operations
Business Acquisition [Line Items]
Gain (Loss) on Disposition of Business	8,700
Gain (Loss) On Disposition Of Business, Net Of Tax	2,800
Disposal Group, Including Discontinued Operation, Accounts, Notes and Loans Receivable, Net	9,900
Goodwill	13,700
Proceeds from Divestiture of Businesses, Gross	45,000
Disposal Group, Including Discontinued Operation, Inventory	7,100
Disposal Group, Including Discontinued Operation, Property, Plant and Equipment	10,700
Accounts payable	$ 6,900

Accounts Receivable and Note _3

Accounts Receivable and Note Receivable - Schedule of Receivables (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Receivables [Abstract]
Trade accounts receivable	$ 275,804	$ 353,709
Less: Allowance for doubtful accounts	(15,114)	(15,522)
Trade accounts receivable, net	260,690	338,187
Other receivables	$ 40,439	$ 40,565

Accounts Receivable and Note _4

Accounts Receivable and Note Receivable (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		12 Months Ended
	Jun. 30, 2022	Dec. 31, 2024	Jun. 30, 2024	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Feb. 20, 2025	Jan. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Trade accounts receivable		$ 275,804		$ 275,804	$ 353,709
Accounts Receivable, Allowance for Credit Loss, Writeoff		3,700
Accounts Receivable Greater than 12 Months Reserved		6,500		6,500
Accounts Receivable Securitization, Deferred Financing Cost		400		400	1,800
Receivable with Imputed Interest, Face Amount								$ 40,000
Note Receivable; Interest Rate; Stated percentage								2.50%
Receivable with Imputed Interest, Net Amount		0		0	14,000
Accounts Receivable, Securitization, Incurred Feeds				9,500	9,100	$ 2,900
Accounts Receivable, Securitization, Deferred Financing Fees				500	600	300
Interest income				6,795	6,809	$ 3,829
P N C Member
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts Receivable Securitization, Maximum Purchase Commitment		150,000		150,000
Accounts Receivable from Securitization		63,800		63,800	$ 82,200
P N C Member | Subsequent Event
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts Receivable Securitization, Maximum Purchase Commitment							$ 160,000
PNC
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts Receivable Securitization, Term	3 years
Greater than 12 months
Accounts, Notes, Loans and Financing Receivable [Line Items]
Trade accounts receivable		$ 9,500		$ 9,500
Harsco Industrial IKG | Disposal Group, Disposed of by Sale, Not Discontinued Operations
Accounts, Notes, Loans and Financing Receivable [Line Items]
Disposal Group, Including Discontinued Operation, Consideration								$ 85,000
Proceeds from Sale of Notes Receivable			$ 17,000
Interest income			$ 2,700

Accounts Receivable and Note _5

Accounts Receivable and Note Receivable - Schedule of Changes in Provisions For Allowance For Credit Loss (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Receivables [Abstract]
Change in provision for expected credit losses	$ 2,821	$ 7,042	$ 330

Accounts Receivable and Note _6

Accounts Receivable and Note Receivable - Factoring Agreements (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Receivables [Abstract]
Receivables Sold under Factoring Agreement	$ 13,300	$ 16,100
Receivables Sold under Factoring Agreement, Program Capacities	$ 18,600	$ 32,600

Accounts Receivable - Schedule

Accounts Receivable - Schedule of Fair Value of Notes Receivable (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Receivables [Abstract]
Receivable with Imputed Interest, Net Amount	$ 0	$ 14,000
Notes Receivable, Fair Value Disclosure	$ 0	$ 15,400

Inventories (Details)

Inventories (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Inventories
Finished goods	$ 14,344	$ 16,171
Work-in-process	15,629	13,081
Raw materials and purchased parts	107,364	114,046
Stores and supplies	44,705	46,071
Total inventories	182,042	189,369
Valued at lower of cost or market:
LIFO basis	96,680	95,203
FIFO basis	18,747	18,685
Average cost basis	66,615	75,481
Total inventories	182,042	189,369
Excess of inventories valued at current costs over LIFO	21,000	32,000
Change in income as a result of LIFO basis inventory valuation over FIFO basis valuation	$ 2,600	$ 0	$ 0

Property, Plant and Equipment_2

Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Property, Plant and Equipment [Line Items]
Gross property, plant and equipment	$ 1,949,978	$ 2,133,143
Less: Accumulated depreciation	(1,285,686)	(1,425,746)
Property, plant and equipment, net	664,292	707,397
Land
Property, Plant and Equipment [Line Items]
Gross property, plant and equipment	$ 94,551	93,793
Land improvements | Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	5 years
Land improvements | Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	20 years
Buildings and improvements
Property, Plant and Equipment [Line Items]
Gross property, plant and equipment	$ 225,688	243,472
Buildings and improvements | Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	10 years
Buildings and improvements | Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	30 years
Machinery and equipment
Property, Plant and Equipment [Line Items]
Gross property, plant and equipment	$ 1,576,298	1,729,637
Machinery and equipment | Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	3 years
Machinery and equipment | Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	20 years
Uncompleted construction
Property, Plant and Equipment [Line Items]
Gross property, plant and equipment	$ 53,441	$ 66,241

Property, Plant and Equipment -

Property, Plant and Equipment - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net	$ 664,292	$ 664,292	$ 707,397
Remeasurement of long-lived assets		10,695	0	$ 0
Property, plant and equipment impairment charge		23,444	14,099	$ 0
China
Property, Plant and Equipment [Line Items]
Property, plant and equipment impairment charge			14,100
United States
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net	338,679	$ 338,679	$ 339,231
Property, plant and equipment impairment charge	13,900
Middle East
Property, Plant and Equipment [Line Items]
Property, plant and equipment impairment charge	$ 9,500

Goodwill and Other Intangible_3

Goodwill and Other Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Goodwill [Roll Forward]
Balance at the beginning of the period	$ 780,978	$ 772,279
Goodwill, Impairment Loss	(13,026)
Foreign currency translation	(9,163)	8,699
Balance at the end of the period	739,758	780,978	$ 772,279
Changes to goodwill	(19,031)
Harsco Environmental
Goodwill [Roll Forward]
Balance at the beginning of the period	388,653	379,954
Goodwill, Impairment Loss	0
Foreign currency translation	(9,163)	8,699
Balance at the end of the period	360,459	388,653	379,954
Changes to goodwill	(19,031)
Clean Earth
Goodwill [Roll Forward]
Balance at the beginning of the period	379,299	379,299
Goodwill, Impairment Loss	0
Foreign currency translation	0	0
Balance at the end of the period	379,299	379,299	379,299
Changes to goodwill	0
Harsco Rail
Goodwill [Roll Forward]
Balance at the beginning of the period	13,026	13,026
Goodwill, Impairment Loss	(13,026)		(104,600)
Foreign currency translation	0	0
Balance at the end of the period	0	$ 13,026	$ 13,026
Changes to goodwill	$ 0

Goodwill and Other Intangible_4

Goodwill and Other Intangible Assets (Details 2) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 492,139	$ 497,610
Accumulated Amortization	193,701	169,627
Intangible assets, net	298,438	327,983
Amortization expense for intangible assets	27,300	28,900	$ 31,400
Estimated amortization expense for the next five years
2025	26,300
2026	26,300
2027	25,000
2028	23,500
2029	22,800
Customer related
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	95,251	102,119
Accumulated Amortization	69,795	66,016
Permits
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	310,236	309,679
Accumulated Amortization	82,799	66,733
Technology related
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	22,880	21,803
Accumulated Amortization	17,477	17,001
Trade names
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	31,514	31,580
Accumulated Amortization	15,142	12,428
Air rights
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	26,139	26,139
Accumulated Amortization	3,979	3,281
Patents
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	162	206
Accumulated Amortization	148	179
Non-compete agreement
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	2,500	2,500
Accumulated Amortization	2,500	2,343
Other
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	3,457	3,584
Accumulated Amortization	$ 1,861	$ 1,646

Goodwill and Other Intangible_5

Goodwill and Other Intangible Assets- Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Goodwill [Line Items]
Goodwill, Impairment Loss	$ 13,026
Goodwill	739,758	$ 780,978	$ 772,279
Impaired asset write-downs	5,259	88	736
Clean Earth
Goodwill [Line Items]
Goodwill, Impairment Loss	0
Goodwill	379,299	379,299	379,299
Impaired asset write-downs	567	0	59
Harsco Environmental
Goodwill [Line Items]
Goodwill, Impairment Loss	0
Goodwill	360,459	388,653	379,954
Impaired asset write-downs	$ 2,771	$ 88	582
Altek Group
Goodwill [Line Items]
Impaired asset write-downs			15,000
Intangible Assets, Net (Excluding Goodwill)			$ 15,300

Debt and Credit Agreements - Sc

Debt and Credit Agreements - Schedule of Long Term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Line of Credit Facility [Line Items]
Long-term Debt	$ 1,431,722	$ 1,416,995
Long-term Debt, Gross	1,444,417	1,428,969
Less: deferred financing costs	12,695	11,974
Current maturities of long-term debt	21,004	15,558
Long-term debt	1,410,718	1,401,437
Revolving Credit Facility
Line of Credit Facility [Line Items]
Long-term Debt	$ 407,000	$ 422,000
Debt, Weighted Average Interest Rate	6.49%	8.12%
New Term Loan
Line of Credit Facility [Line Items]
Long-term Debt	$ 482,500	$ 487,500
Debt, Weighted Average Interest Rate	6.72%	7.72%
Senior Notes | Revolving Credit Facility
Line of Credit Facility [Line Items]
Current maturities of long-term debt	$ 5,000
Notes Payable, Other Payables
Line of Credit Facility [Line Items]
Long-term Debt	$ 79,917	$ 44,469
Debt, Weighted Average Interest Rate	7.14%	6.11%
5.75% notes due May 15,2018 | Senior Notes
Line of Credit Facility [Line Items]
Long-term Debt	$ 475,000	$ 475,000
Debt Instrument, Interest Rate, Stated Percentage	5.75%

Debt and Credit Agreements - _2

Debt and Credit Agreements - Schedule of Maturities of Long Term Debt (Details) $ in Thousands	Dec. 31, 2024 USD ($)
Maturities of Long-term Debt [Abstract]
2026	$ 50,019
2027	494,421
2028	480,873
2029	$ 387,026

Debt and Credit Agreements - Na

Debt and Credit Agreements - Narrative (Details) $ in Thousands	1 Months Ended	12 Months Ended
	Sep. 30, 2024	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Feb. 14, 2025
Line of Credit Facility [Line Items]
Interest Paid, Including Capitalized Interest, Operating and Investing Activities		$ 109,500	$ 101,500	$ 73,400
Loss on early extinguishment of debt		$ 0	$ 0	$ 2,254
Short-term Debt, Weighted Average Interest Rate, at Point in Time		6.09%	6.10%
Subsequent Event
Line of Credit Facility [Line Items]
Debt Instrument, Covenant, EBITDA Ratio, Quarterly Decrease					0.25
Debt Covenant Ratio, Period One
Line of Credit Facility [Line Items]
Debt Instrument, Covenant, EBITDA Ratio, Maximum	4.75
Debt Instrument, Covenant, Interest Rate Coverage Ratio, Maximum	2.75
Debt Covenant Ratio, Period One | Subsequent Event
Line of Credit Facility [Line Items]
Debt Instrument, Covenant, EBITDA Ratio, Maximum					4.75
Debt Instrument, Covenant, Interest Rate Coverage Ratio, Maximum					2.75
Debt Covenant Ratio, Period Two
Line of Credit Facility [Line Items]
Debt Instrument, Covenant, EBITDA Ratio, Maximum	4.50
Debt Covenant Ratio, Period Two | Subsequent Event
Line of Credit Facility [Line Items]
Debt Instrument, Covenant, EBITDA Ratio, Maximum					5
Debt Covenant Ratio, Period Three | Subsequent Event
Line of Credit Facility [Line Items]
Debt Instrument, Covenant, EBITDA Ratio, Maximum					4
Debt Covenant Ratio, Period Four
Line of Credit Facility [Line Items]
Debt Instrument, Covenant, Interest Rate Coverage Ratio, Maximum	4
Debt Covenant Ratio, Period Four | Subsequent Event
Line of Credit Facility [Line Items]
Debt Instrument, Covenant, Interest Rate Coverage Ratio, Maximum					2.50
Debt Covenant Ratio, Period Five
Line of Credit Facility [Line Items]
Debt Instrument, Covenant, EBITDA Ratio, Maximum	4.25
Debt Covenant Ratio, Period Six
Line of Credit Facility [Line Items]
Debt Instrument, Covenant, Interest Rate Coverage Ratio, Maximum	3
Senior Secured Credit Facility
Line of Credit Facility [Line Items]
Net Debt to Consolidated Adjusted EBITDA Ratio		4.07
Consolidated Adjusted EBITDA To Consolidated Interest Charges Ratio		3.05
Increase to net debt		$ 227,600
Decrease to adjusted EBITDA		33,100
Increase to interest expense		12,100
Revolving Credit Facility | Line of Credit [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		625,000
Debt Issuance Costs, Gross		300
Long-term Line of Credit		50,000
Unamortized Debt Issuance Expense		$ 4,400
Revolving Credit Facility | Extended Revolving Credit Facility | Line of Credit [Member] | Minimum | Base Rate
Line of Credit Facility [Line Items]
Basis spread on variable rate	0.75%
Revolving Credit Facility | Extended Revolving Credit Facility | Line of Credit [Member] | Minimum | Secured Overnight Financing Rate (SOFR)
Line of Credit Facility [Line Items]
Basis spread on variable rate	1.75%
Revolving Credit Facility | Extended Revolving Credit Facility | Line of Credit [Member] | Maximum | Base Rate
Line of Credit Facility [Line Items]
Basis spread on variable rate	1.25%
Revolving Credit Facility | Extended Revolving Credit Facility | Line of Credit [Member] | Maximum | Secured Overnight Financing Rate (SOFR)
Line of Credit Facility [Line Items]
Basis spread on variable rate	2.25%
Revolving Credit Facility | Existing Revolving Credit Facility | Line of Credit [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Floor Interest Rate		0%
Revolving Credit Facility | Existing Revolving Credit Facility | Line of Credit [Member] | Minimum | Base Rate
Line of Credit Facility [Line Items]
Basis spread on variable rate	0.50%
Revolving Credit Facility | Existing Revolving Credit Facility | Line of Credit [Member] | Minimum | Secured Overnight Financing Rate (SOFR)
Line of Credit Facility [Line Items]
Basis spread on variable rate	1.50%
Revolving Credit Facility | Existing Revolving Credit Facility | Line of Credit [Member] | Maximum | Base Rate
Line of Credit Facility [Line Items]
Basis spread on variable rate	1.75%
Revolving Credit Facility | Existing Revolving Credit Facility | Line of Credit [Member] | Maximum | Secured Overnight Financing Rate (SOFR)
Line of Credit Facility [Line Items]
Basis spread on variable rate	2.75%

Debt and Credit Agreements - Ou

Debt and Credit Agreements - Outstanding Amounts Under Revolving Credit Facility (Details) - Line of Credit [Member] $ in Thousands	Dec. 31, 2024 USD ($)
Debt Instrument [Line Items]
Line of Credit Facility, Remaining Borrowing Capacity	$ 238,154
Line of Credit Facility, Maximum Borrowing Capacity	675,000
Long-term Line of Credit	407,000
Letters of Credit Outstanding, Amount	$ 29,846

Debt and Credit Agreements - _3

Debt and Credit Agreements - Schedule of Facility Fees and Debt-Related Income (Expense) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Schedule of Facility Fees and Debt-Related Income [Line Items]
Loss on early extinguishment of debt	$ 0	$ 0	$ 2,254
Facility fees and debt-related income (expense)	(11,265)	(10,762)	(2,956)
Facility Fees and Debt-Related Income (Expense)
Schedule of Facility Fees and Debt-Related Income [Line Items]
Loss on early extinguishment of debt	(325)	0	2,254
Unused Debt Commitment And Amendment Fees	0	(12)	(1,696)
Securitization And Factoring Fees	$ (10,940)	$ (10,750)	$ (3,514)

Leases - Supplemental Income St

Leases - Supplemental Income Statement Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Leases [Abstract]
Finance Lease, Right-of-Use Asset, Amortization	$ 12,785	$ 7,957	$ 3,938
Finance Lease, Interest Expense	4,318	2,036	784
Operating Lease, Cost	38,702	38,062	35,290
Variable Lease, Cost	54,475	54,432	52,050
Sublease Income	(7)	(7)	(6)
Lease, Cost	$ 110,273	$ 102,480	$ 92,056

Leases - Supplemental Cash Flow

Leases - Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Leases [Abstract]
Operating Lease, Payments	$ 37,120	$ 37,880	$ 34,420
Finance Lease, Interest Payment on Liability	4,203	1,914	798
Finance Lease, Principal Payments	12,316	7,736	3,975
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	21,895	27,951	32,817
Right-of-Use Asset Obtained in Exchange for Finance Lease Liability	$ 49,316	$ 27,128	$ 11,175

Leases - Supplemental Balance S

Leases - Supplemental Balance Sheet Information (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Leases [Abstract]
Right-of-use assets, net	$ 92,153	$ 102,891
Operating Lease, Liability, Current	26,049	28,775
Operating Lease, Liability, Noncurrent	$ 67,998	$ 75,476
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Property, Plant and Equipment, Net	Property, Plant and Equipment, Net
Finance Lease, Right-of-Use Asset	$ 73,734	$ 43,151
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Current maturities of long-term debt	Current maturities of long-term debt
Finance Lease, Liability, Current	$ 16,004	$ 9,723
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Long-term debt	Long-term debt
Finance Lease, Liability, Noncurrent	$ 63,913	$ 33,911

Leases - Supplemental Lease Inf

Leases - Supplemental Lease Information (Details)	Dec. 31, 2024	Dec. 31, 2023
Leases [Abstract]
Operating Lease, Weighted Average Remaining Lease Term	6 years 11 months 23 days	7 years 10 days
Finance Lease, Weighted Average Remaining Lease Term	5 years 3 months 7 days	5 years 3 months 29 days
Operating Lease, Weighted Average Discount Rate, Percent	6.70%	6.30%
Finance Lease, Weighted Average Discount Rate, Percent	7.20%	6.40%

Leases - Schedule of Future Lea

Leases - Schedule of Future Lease Maturities (Details) $ in Thousands	Dec. 31, 2024 USD ($)
Leases [Abstract]
Lessee, Operating Lease, Liability, Payments, Due Next Twelve Months	$ 32,934
Finance Lease, Liability, Payments, Due Next Twelve Months	20,998
Lessee, Operating Lease, Liability, Payments, Due Year Two	25,516
Finance Lease, Liability, Payments, Due Year Two	19,462
Lessee, Operating Lease, Liability, Payments, Due Year Three	18,456
Finance Lease, Liability, Payments, Due Year Three	17,488
Lessee, Operating Lease, Liability, Payments, Due Year Four	12,803
Finance Lease, Liability, Payments, Due Year Four	15,525
Lessee, Operating Lease, Liability, Payments, Due Year Five	8,724
Finance Lease, Liability, Payments, Due Year Five	10,938
Lessee, Operating Lease, Liability, Payments, Due after Year Five	41,883
Finance Lease, Liability, Payments, Due after Year Five	11,805
Lessee, Operating Lease, Liability, Payments, Due	140,316
Finance Lease, Liability, Payment, Due	96,216
Lessee, Operating Lease, Liability, Undiscounted Excess Amount	(32,030)
Finance Lease, Liability, Undiscounted Excess Amount	(16,299)
Operating Lease, Liability	108,286
Finance Lease, Liability	79,917
Operating lease, liability, future renewal agreement	$ 14,000

Leases - Narrative (Details)

Leases - Narrative (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2024 USD ($)
Minimum
Operating Leased Assets [Line Items]
Operating And Finance Leases, Excluding Short Term Leases, Weighted-Average Remaining Lease Term	1 year
Maximum
Operating Leased Assets [Line Items]
Operating And Finance Leases, Excluding Short Term Leases, Weighted-Average Remaining Lease Term	26 years
Clean Earth
Operating Leased Assets [Line Items]
Finance lease obligations, not yet commenced	$ 27,000

Employee Benefit Plans (Details

Employee Benefit Plans (Details) - Pension Plan - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
U.S. Plans
Defined Contribution Plan [Abstract]
Discretionary contributions	$ 0	$ 0	$ 0
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	0	0	0
Interest cost	9,676,000	10,173,000	5,716,000
Expected return on plan assets	(8,944,000)	(7,000,000)	(10,795,000)
Recognized prior service costs	0	0	0
Recognized losses	4,179,000	4,601,000	4,732,000
Settlement/curtailment loss (gain)	0	0	0
Defined benefit plans pension cost	4,911,000	7,774,000	(347,000)
Multiemployer plans	570,000	595,000	642,000
Defined contribution plans	9,985,000	8,468,000	7,082,000
Net periodic pension cost, U.S. Plans	$ 15,466,000	16,837,000	7,377,000
U.S. Plans | Maximum
Defined Contribution Plan [Abstract]
Employer matching contribution (as a percent)	4%
International Plans
Defined Contribution Plan [Abstract]
Additional contribution towards insurance and administrative costs (as a percent)	2%
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	$ 1,322,000	1,245,000	2,029,000
Interest cost	29,409,000	30,220,000	16,637,000
Expected return on plan assets	(33,049,000)	(31,281,000)	(39,179,000)
Recognized prior service costs	492,000	520,000	534,000
Recognized losses	15,060,000	14,316,000	13,060,000
Settlement/curtailment loss (gain)	(1,125,000)	(42,000)	(33,000)
Defined benefit plans pension cost	12,109,000	14,978,000	(6,952,000)
Multiemployer plans	1,241,000	1,209,000	1,114,000
Defined contribution plans	5,690,000	5,396,000	5,111,000
Net periodic pension cost, International Plans	$ 19,040,000	$ 21,583,000	$ (727,000)
International Plans | Maximum
Defined Contribution Plan [Abstract]
Employer matching contribution (as a percent)	6%

Employee Benefit Plans (Detai_2

Employee Benefit Plans (Details 2) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position [Abstract]
Retirement plan assets	$ 73,745	$ 44,517
Noncurrent liabilities	$ 27,019	$ 45,087
Pension Plan
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rates	4.80%	5.10%	2.10%
Expected long-term rates of return on plan assets	5.70%	5.50%	4.70%
Expected long-term rates of return on plan assets for next year (as a percent)	5.10%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rates	5.50%	4.80%
U.S. Plans | Pension Plan
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation at beginning of year	$ 209,177	$ 209,182
Service cost	0	0	$ 0
Interest cost	9,676	10,173	5,716
Plan participants' contributions	0	0
Amendments	0	0
Actuarial loss	(17,591)	5,736
Settlements/curtailments	0	0
Benefits paid	(14,867)	(15,914)
Effect of foreign currency	0	0
Benefit obligation at end of year	186,395	209,177	209,182
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	180,927	177,044
Actual return on plan assets	9,931	18,123
Employer contributions	7,301	1,674
Plan participants' contributions	0	0
Settlements/curtailments	0	0
Benefits paid	(14,867)	(15,914)
Effect of foreign currency	0	0
Fair value of plan assets at end of year	183,292	180,927	$ 177,044
Funded status at end of year	(3,103)	(28,250)
Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position [Abstract]
Retirement plan assets	9,917	0
Current liabilities	1,713	1,832
Noncurrent liabilities	11,307	26,418
Total accumulated other comprehensive loss before tax	72,260	95,016
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax [Abstract]
Net actuarial loss	72,260	95,016
Prior service cost	0	0
Total accumulated other comprehensive loss before tax	72,260	$ 95,016
Pension and Other Postretirement Benefit Plans, Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year [Abstract]
Estimate of expected contributions in next fiscal year	3,000
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2021	19,700
2022	15,600
2023	15,400
2024	15,200
2025	15,000
2026-2030	$ 71,500
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rates	5%	5.30%	2.70%
Expected long-term rates of return on plan assets	7%	7%	6.30%
Expected long-term rates of return on plan assets for next year (as a percent)	6.80%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rates	5.50%	5%
Highest yield U.S. dollar-denominated, AA-graded corporate bonds excluded from yield curve universe (as a percent)	10%
Lowest yield U.S. dollar-denominated, AA-graded corporate bonds excluded from yield curve universe (as a percent)	10%
International Plans | Pension Plan
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation at beginning of year	$ 642,648	$ 598,302
Service cost	1,322	1,245	$ 2,029
Interest cost	29,409	30,220	16,637
Plan participants' contributions	12	13
Amendments	0	74
Actuarial loss	(57,451)	17,896
Settlements/curtailments	(1,363)	(203)
Benefits paid	(36,691)	(36,705)
Effect of foreign currency	(15,803)	31,806
Benefit obligation at end of year	562,083	642,648	598,302
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	669,021	608,672
Actual return on plan assets	(20,357)	40,587
Employer contributions	14,778	24,715
Plan participants' contributions	12	13
Settlements/curtailments	(192)	(203)
Benefits paid	(36,691)	(36,705)
Effect of foreign currency	(14,904)	31,942
Fair value of plan assets at end of year	611,667	669,021	$ 608,672
Funded status at end of year	49,584	26,373
Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position [Abstract]
Retirement plan assets	63,879	44,585
Current liabilities	507	726
Noncurrent liabilities	13,788	17,486
Total accumulated other comprehensive loss before tax	332,026	358,631
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax [Abstract]
Net actuarial loss	324,661	350,469
Prior service cost	7,365	8,162
Total accumulated other comprehensive loss before tax	332,026	$ 358,631
Pension and Other Postretirement Benefit Plans, Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year [Abstract]
Estimate of expected contributions in next fiscal year	800
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2021	36,400
2022	37,000
2023	37,100
2024	38,200
2025	39,500
2026-2030	$ 192,900
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rates	4.80%	5%	1.90%
Expected long-term rates of return on plan assets	5.30%	5.10%	4.40%
Expected long-term rates of return on plan assets for next year (as a percent)	4.60%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rates	5.40%	4.80%

Employee Benefit Plans (Detai_3

Employee Benefit Plans (Details 3) - Pension Plan $ in Thousands	12 Months Ended
	Dec. 31, 2024 USD ($) market shares	Dec. 31, 2023 USD ($) shares	Dec. 31, 2022 USD ($)
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Expected long-term rates of return on plan assets for next year (as a percent)	5.10%
Expected long-term rates of return on plan assets	5.70%	5.50%	4.70%
U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation	$ 186,400	$ 209,200
Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets [Abstract]
Projected benefit obligation	13,000	209,200
Accumulated benefit obligation	13,000	209,200
Fair value of plan assets	$ 0	$ 180,900
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Number of capital market results simulated in the model for expected return on plan assets | market	1,000
Period for which results of capital markets are simulated	20 years
Expected long-term rates of return on plan assets for next year (as a percent)	6.80%
Expected long-term rates of return on plan assets	7%	7%	6.30%
Number of shares of Company's common stock included in plan assets | shares	310,000	310,000
Fair values of plan assets	$ 183,292	$ 180,927	$ 177,044
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	180,927	177,044
Employer contributions	7,301	1,674
Fair value of plan assets at end of year	$ 183,292	$ 180,927	$ 177,044
U.S. Plans | Domestic equity securities
Defined Benefit Plan, Information about Plan Assets [Abstract]
Percentage of Plan Assets at December 31	8.80%	10.70%
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	$ 2,388	$ 2,791
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	2,791
Fair value of plan assets at end of year	$ 2,388	2,791
U.S. Plans | Domestic equity securities | Minimum
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Target Long-Term Allocation (less than 5% for Cash and cash equivalents)	4%
U.S. Plans | Domestic equity securities | Maximum
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Target Long-Term Allocation (less than 5% for Cash and cash equivalents)	14%
U.S. Plans | Domestic mutual funds—equities
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	$ 13,748	16,583
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	16,583
Fair value of plan assets at end of year	$ 13,748	$ 16,583
U.S. Plans | International equity securities
Defined Benefit Plan, Information about Plan Assets [Abstract]
Percentage of Plan Assets at December 31	21%	24.30%
U.S. Plans | International equity securities | Minimum
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Target Long-Term Allocation (less than 5% for Cash and cash equivalents)	17%
U.S. Plans | International equity securities | Maximum
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Target Long-Term Allocation (less than 5% for Cash and cash equivalents)	27%
U.S. Plans | International equities—mutual funds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	$ 38,398	$ 43,994
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	43,994
Fair value of plan assets at end of year	$ 38,398	$ 43,994
U.S. Plans | Harsco common stock
Defined Benefit Plan, Information about Plan Assets [Abstract]
Percentage of Plan Assets at December 31	1.30%	1.50%
U.S. Plans | Fixed income securities
Defined Benefit Plan, Information about Plan Assets [Abstract]
Percentage of Plan Assets at December 31	65.40%	52.80%
U.S. Plans | Fixed income securities | Minimum
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Target Long-Term Allocation (less than 5% for Cash and cash equivalents)	61%
U.S. Plans | Fixed income securities | Maximum
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Target Long-Term Allocation (less than 5% for Cash and cash equivalents)	71%
U.S. Plans | U.S. Treasuries and collateralized securities
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	$ 15,673	$ 13,920
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	13,920
Fair value of plan assets at end of year	15,673	13,920
U.S. Plans | Mutual funds - bonds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	104,166	81,634
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	81,634
Fair value of plan assets at end of year	$ 104,166	$ 81,634
U.S. Plans | Other
Defined Benefit Plan, Information about Plan Assets [Abstract]
Percentage of Plan Assets at December 31	3.90%	11.30%
U.S. Plans | Other | Minimum
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Target Long-Term Allocation (less than 5% for Cash and cash equivalents)	0%
U.S. Plans | Other | Maximum
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Target Long-Term Allocation (less than 5% for Cash and cash equivalents)	8%
U.S. Plans | Other mutual funds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		$ 4,913
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	$ 4,913
Fair value of plan assets at end of year		$ 4,913
U.S. Plans | Cash and cash equivalents
Defined Benefit Plan, Information about Plan Assets [Abstract]
Percentage of Plan Assets at December 31	0.90%	0.90%
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	$ 1,681	$ 1,661
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	1,661
Fair value of plan assets at end of year	$ 1,681	1,661
U.S. Plans | Cash and cash equivalents | Maximum
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Target Long-Term Allocation (less than 5% for Cash and cash equivalents)	5%
U.S. Plans | Partnership [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	$ 7,238	15,431
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	15,431
Fair value of plan assets at end of year	7,238	15,431
U.S. Plans | Defined Benefit Plan, Equity Securities, Common Stock, Employer, Related Party [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Value of shares of Company's common stock included in plan assets	2,400	2,800
U.S. Plans | Level 1
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	160,381	151,576
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	151,576
Fair value of plan assets at end of year	160,381	151,576
U.S. Plans | Level 1 | Domestic equity securities
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	2,388	2,791
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	2,791
Fair value of plan assets at end of year	2,388	2,791
U.S. Plans | Level 1 | Domestic mutual funds—equities
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	13,748	16,583
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	16,583
Fair value of plan assets at end of year	13,748	16,583
U.S. Plans | Level 1 | International equities—mutual funds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	38,398	43,994
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	43,994
Fair value of plan assets at end of year	38,398	43,994
U.S. Plans | Level 1 | U.S. Treasuries and collateralized securities
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0
Fair value of plan assets at end of year	0	0
U.S. Plans | Level 1 | Mutual funds - bonds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	104,166	81,634
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	81,634
Fair value of plan assets at end of year	104,166	81,634
U.S. Plans | Level 1 | Other mutual funds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		4,913
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	4,913
Fair value of plan assets at end of year		4,913
U.S. Plans | Level 1 | Cash and cash equivalents
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	1,681	1,661
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	1,661
Fair value of plan assets at end of year	1,681	1,661
U.S. Plans | Level 1 | Partnership [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0
Fair value of plan assets at end of year	0	0
U.S. Plans | Level 2
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	15,673	13,920
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	13,920
Fair value of plan assets at end of year	15,673	13,920
U.S. Plans | Level 2 | Domestic equity securities
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0
Fair value of plan assets at end of year	0	0
U.S. Plans | Level 2 | Domestic mutual funds—equities
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0
Fair value of plan assets at end of year	0	0
U.S. Plans | Level 2 | International equities—mutual funds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0
Fair value of plan assets at end of year	0	0
U.S. Plans | Level 2 | U.S. Treasuries and collateralized securities
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	15,673	13,920
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	13,920
Fair value of plan assets at end of year	15,673	13,920
U.S. Plans | Level 2 | Mutual funds - bonds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0
Fair value of plan assets at end of year	0	0
U.S. Plans | Level 2 | Other mutual funds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0
Fair value of plan assets at end of year		0
U.S. Plans | Level 2 | Cash and cash equivalents
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0
Fair value of plan assets at end of year	0	0
U.S. Plans | Level 2 | Partnership [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0
Fair value of plan assets at end of year	0	0
U.S. Plans | Fair Value Measured at Net Asset Value Per Share [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	7,238	15,431
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	15,431
Fair value of plan assets at end of year	7,238	15,431
U.S. Plans | Fair Value Measured at Net Asset Value Per Share [Member] | Domestic equity securities
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0
Fair value of plan assets at end of year	0	0
U.S. Plans | Fair Value Measured at Net Asset Value Per Share [Member] | Domestic mutual funds—equities
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0
Fair value of plan assets at end of year	0	0
U.S. Plans | Fair Value Measured at Net Asset Value Per Share [Member] | International equities—mutual funds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0
Fair value of plan assets at end of year	0	0
U.S. Plans | Fair Value Measured at Net Asset Value Per Share [Member] | U.S. Treasuries and collateralized securities
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0
Fair value of plan assets at end of year	0	0
U.S. Plans | Fair Value Measured at Net Asset Value Per Share [Member] | Mutual funds - bonds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0
Fair value of plan assets at end of year	0	0
U.S. Plans | Fair Value Measured at Net Asset Value Per Share [Member] | Other mutual funds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0
Fair value of plan assets at end of year		0
U.S. Plans | Fair Value Measured at Net Asset Value Per Share [Member] | Cash and cash equivalents
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0
Fair value of plan assets at end of year	0	0
U.S. Plans | Fair Value Measured at Net Asset Value Per Share [Member] | Partnership [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	7,238	15,431
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	15,431
Fair value of plan assets at end of year	7,238	15,431
International Plans
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation	558,400	637,600
Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets [Abstract]
Projected benefit obligation	22,100	27,800
Accumulated benefit obligation	19,900	24,100
Fair value of plan assets	$ 7,900	$ 9,700
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Expected long-term rates of return on plan assets for next year (as a percent)	4.60%
Expected long-term rates of return on plan assets	5.30%	5.10%	4.40%
Fair values of plan assets	$ 611,667	$ 669,021	$ 608,672
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	669,021	608,672
Employer contributions	14,778	24,715
Fair value of plan assets at end of year	$ 611,667	$ 669,021	$ 608,672
International Plans | Equity Securities [Member]
Defined Benefit Plan, Information about Plan Assets [Abstract]
Percentage of Plan Assets at December 31	0.90%	10.80%
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Target Long-Term Allocation (less than 5% for Cash and cash equivalents)	12.40%
International Plans | Mutual funds - equities
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	$ 5,342	$ 71,980
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	71,980
Fair value of plan assets at end of year	$ 5,342	$ 71,980
International Plans | Fixed income securities
Defined Benefit Plan, Information about Plan Assets [Abstract]
Percentage of Plan Assets at December 31	95%	83.30%
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Target Long-Term Allocation (less than 5% for Cash and cash equivalents)	82.80%
International Plans | Mutual funds - bonds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	$ 576,540	$ 552,898
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	552,898
Fair value of plan assets at end of year	576,540	552,898
International Plans | Insurance contracts
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	4,394	4,631
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	4,631
Fair value of plan assets at end of year	$ 4,394	$ 4,631
International Plans | Other
Defined Benefit Plan, Information about Plan Assets [Abstract]
Percentage of Plan Assets at December 31	2.30%	5.40%
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Target Long-Term Allocation (less than 5% for Cash and cash equivalents)	4.80%
International Plans | Other mutual funds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	$ 14,244	$ 36,263
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	36,263
Fair value of plan assets at end of year	$ 14,244	$ 36,263
International Plans | Cash and cash equivalents
Defined Benefit Plan, Information about Plan Assets [Abstract]
Percentage of Plan Assets at December 31	1.80%	0.50%
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Target Long-Term Allocation (less than 5% for Cash and cash equivalents)	0%
Fair values of plan assets	$ 11,147	$ 3,249
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	3,249
Fair value of plan assets at end of year	11,147	3,249
International Plans | Level 1
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	11,147	3,249
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	3,249
Fair value of plan assets at end of year	11,147	3,249
International Plans | Level 1 | Mutual funds - equities
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0
Fair value of plan assets at end of year	0	0
International Plans | Level 1 | Mutual funds - bonds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0
Fair value of plan assets at end of year	0	0
International Plans | Level 1 | Insurance contracts
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0
Fair value of plan assets at end of year	0	0
International Plans | Level 1 | Other mutual funds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0
Fair value of plan assets at end of year	0	0
International Plans | Level 1 | Cash and cash equivalents
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	11,147	3,249
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	3,249
Fair value of plan assets at end of year	11,147	3,249
International Plans | Level 2
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	600,520	665,772
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	665,772
Fair value of plan assets at end of year	600,520	665,772
International Plans | Level 2 | Mutual funds - equities
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	5,342	71,980
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	71,980
Fair value of plan assets at end of year	5,342	71,980
International Plans | Level 2 | Mutual funds - bonds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	576,540	552,898
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	552,898
Fair value of plan assets at end of year	576,540	552,898
International Plans | Level 2 | Insurance contracts
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	4,394	4,631
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	4,631
Fair value of plan assets at end of year	4,394	4,631
International Plans | Level 2 | Other mutual funds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	14,244	36,263
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	36,263
Fair value of plan assets at end of year	14,244	36,263
International Plans | Level 2 | Cash and cash equivalents
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets	0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0
Fair value of plan assets at end of year	$ 0	$ 0
International, Other Than United Kingdom [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Pension plan assets as a percentage of international plan assets	6%
United Kingdom
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Expected long-term rates of return on plan assets for next year (as a percent)	4.60%	5.30%
Pension plan assets as a percentage of international plan assets	94%

Employee Benefit Plans (Detai_4

Employee Benefit Plans (Details 4) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Retirement Benefits [Abstract]
Contributions By The Company	$ 1.8	$ 1.9	$ 1.9

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Income from continuing operations before income taxes and equity income
U.S.	$ (61,205)	$ (19,598)	$ (171,625)
International	(40,465)	(33,072)	3,728
Income (loss) from continuing operations before income taxes and equity income	(101,670)	(52,670)	(167,897)
Currently payable:
U.S. federal	897	(823)	0
U.S. state	2,701	3,591	975
International	24,884	23,801	16,428
Total income taxes currently payable	28,482	26,569	17,403
Deferred U.S. federal	(5,667)	2,735	(12,655)
Deferred U.S. state	(2,997)	(1,550)	(1,935)
Deferred international	(2,752)	3,112	2,043
Total income tax expense from continuing operations	17,066	30,866	4,856
Cash payments for income taxes, including taxes on gain or loss from discontinued business	$ 29,100	$ 20,100	$ 20,900

Income Taxes (Details 2)

Income Taxes (Details 2) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Income Tax Disclosure [Line Items]
Foreign earnings before tax	$ (40,465)	$ (33,072)	$ 3,728
Differences on international earnings and remittances	29,000	26,400
Income Tax Expense (Benefit)	17,066	30,866	4,856
Total international income tax expense	24,884	23,801	16,428
Operating loss carryforwards	128,412	118,309
Valuation Allowance	192,745	177,888
Interest and penalties recognized	0	(100)	400
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	1,300	1,300	1,300
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Amount of Unrecorded Benefit	600
Current Foreign Tax Expense (Benefit)	22,100	26,900
Impaired asset write-downs	5,259	88	736
Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions	2,100
Increase (decrease) in valuation allowance	(5,400)
Harsco Environmental
Income Tax Disclosure [Line Items]
Impaired asset write-downs	2,771	88	582
Clean Earth
Income Tax Disclosure [Line Items]
Impaired asset write-downs	567	0	59
Altek Group
Income Tax Disclosure [Line Items]
Impaired asset write-downs			$ 15,000
HE Sites
Income Tax Disclosure [Line Items]
Income Tax Expense (Benefit)	3,700	0
Impaired asset write-downs	14,100
International operations
Income Tax Disclosure [Line Items]
Operating loss carryforwards	116,000
Operating loss carryforwards not subject to expiration	107,900
Operating losses subject to expiration	8,100
U.S. state
Income Tax Disclosure [Line Items]
Operating loss carryforwards	12,400
United States
Income Tax Disclosure [Line Items]
Differences on international earnings and remittances	$ 300	$ 300

Income Taxes (Details 3)

Income Taxes (Details 3) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Effective Income Tax Rate Reconciliation, Percent [Abstract]
U.S. federal income tax expense (benefit), at statutory tax rate of 21%	$ (21,350)	$ (11,060)	$ (35,259)
U.S. state income taxes, net of federal income tax benefit	(1,296)	624	(644)
U.S. other domestic deductions and credits	(1,084)	(1,275)	(1,216)
Difference in effective tax rates on international earnings and remittances	(29,019)	(26,372)	(11,166)
Uncertain tax position contingencies and settlements	(51)	(768)	(290)
Changes in realization of deferred tax assets	10,366	14,498	8,262
U.S. non-deductible expenses	3,663	278	24
Nondeductible goodwill charges	3,676	0	19,548
PP&E / Intangible asset impairment	0	2,961	3,150
State deferred tax rate changes	(63)	304	343
Foreign derived intangible income deduction	(1,675)	(2,199)	(1,792)
Share-based compensation	1,967	1,131	1,564
Total income tax expense from continuing operations	$ 17,066	$ 30,866	$ 4,856
Annual effective income tax rate	(16.80%)	(58.60%)	(2.90%)
International	$ (40,465)	$ (33,072)	$ 3,728
Income Tax Expense (Benefit)	17,066	30,866	4,856
Current Foreign Tax Expense (Benefit)	22,100	26,900
Differences on international earnings and remittances	29,000	26,400
U.S.	(61,205)	(19,598)	(171,625)
Income Tax Expense (Benefit), Increase (Decrease) From Prior Year	5,100	4,000
Effective Income Tax Rate Reconciliation, Deduction, Other, Amount	$ (6,106)	$ 0	$ 0

Income Taxes (Details 4)

Income Taxes (Details 4) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Operating Loss Carryforwards [Line Items]
U.S.	$ 61,205	$ 19,598	$ 171,625
Interest and penalties recognized	0	(100)	$ 400
Asset
Depreciation and amortization	0	0
Deferred Tax Assets. Right-of-use assets	0	0
Deferred Tax Liability, Operating lease liabilities	0	0
Operating lease liabilities	23,302	25,752
Deferred Tax Liabilities, Deferred Expense, Reserves and Accruals	0	0
Expense accruals	26,428	33,810
Deferred Tax Liabilities, Inventory	0	0
Inventories	2,324	3,779
Deferred Tax Liability, Tax Deferred Expense, Reserve and Accrual, Accounts Receivable, Allowance for Credit Loss	0	0
Provision for receivables	2,345	3,801
Deferred Tax Assets, Deferred Income	11,582	6,513
Deferred Tax Liability, Operating loss carryforwards	0	0
Operating loss carryforwards	128,412	118,309
Deferred Tax Liability, Tax credit carryforwards	0	0
Tax credit carryforwards	13,480	15,298
Pensions	0	0
Deferred Tax Liabilities, Unrealized Currency Loss	0	1,171
Currency adjustments	98	0
Section 163(j) disallowed interest expense	40,054	25,937
Deferred Tax Liabilities, Deferred Expense, Capitalized Research and Development Costs	0	0
Research and development	8,236	6,013
Deferred Tax Liability, Tax Deferred Expense, Compensation and Benefits, Share-Based Compensation Cost	0	0
Stock based compensation	7,968	7,387
Other	1,881	0
Subtotal	266,110	246,599
Deferred Tax Liability, Valuation Allowance	0	0
Valuation allowance	(192,745)	(177,888)
Total deferred income taxes	73,365	68,711
Liability
Depreciation and amortization	47,816	53,577
Right-of-use assets	22,851	25,417
Deferred revenue	0	0
Deferred Tax Liabilities, Other	0	812
Total deferred income taxes	82,583	81,576
Valuation Allowance, Deferred Tax Asset, Decrease From Pension Adjustment	15,000
Increase from unrealized current year losses in foreign jurisdictions	14,100
Foreign Currency Translation Adjustment, Valuation Allowance Reduction, Reduction to Deferred Tax Assets	$ 7,200
Dividend Received Deduction, Tax Act, Percent	100%
Deferred Tax Liability, Tax Deferred Expense, Compensation and Benefits, Pensions	$ 11,916	599
Deferred Tax Liability, Disallowed Interest Expense	0	$ 0
Capital Loss Carryforward
Liability
Tax Credit Carryforward, Amount	1,100,000
International operations
Operating Loss Carryforwards [Line Items]
Operating losses subject to expiration	8,100
Operating loss carryforwards not subject to expiration	107,900
Asset
Operating loss carryforwards	116,000
U.S. state
Asset
Operating loss carryforwards	12,400
U.S. state | Tax Years 2021 Through 2025 [Member]
Asset
Operating loss carryforwards	1,600
U.S. state | Tax Years 2026 Through 2030 [Member]
Asset
Operating loss carryforwards	2,000
U.S. state | Tax Years 2031 Through 2035 [Member]
Asset
Operating loss carryforwards	3,100
U.S. state | Tax Years 2036 Through 2040 [Member]
Asset
Operating loss carryforwards	$ 5,700

Income Taxes (Details 5)

Income Taxes (Details 5) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Unrecognized Tax Benefits [Roll Forward]
Balance at the beginning of the period	$ 2,125	$ 2,792	$ 3,127
Additions for tax positions related to the current year (includes currency translation adjustment)	228	439	189
Statutes of limitations expirations	(577)	(1,106)	(524)
Balance at the end of the period	1,776	2,125	2,792
Reconciliation of Deferred Income Tax Benefits [Roll Forward]
Balance at beginning of period	(17)	(21)	(22)
Additions for tax positions related to the current year (includes currency translation adjustment)	9	(1)	(1)
Statutes of limitation expirations	0	5	2
Balance at the end of the period	(8)	(17)	(21)
Reconciliation of Net Unrecognized Tax Benefits [Roll Forward]
Balance at the beginning of the period	2,108	2,771	3,105
Additions for tax positions related to the current year (includes currency translation adjustment)	237	438	188
Statutes of limitation expirations	(577)	(1,101)	(522)
Balance at the end of the period	$ 1,768	$ 2,108	$ 2,771

Commitments and Contingencies -

Commitments and Contingencies - Schedule of Loss Contingencies by Contingency (Details) - USD ($)	Dec. 31, 2024	Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Current Portion of Environmental Liabilities	$ 11,815,000	$ 7,540,000
Total environmental liabilities	58,400,000	33,222,000
Accrued Environmental Loss Contingencies, Noncurrent	$ 46,585,000	$ 25,682,000

Commitments and Contingencies (

Commitments and Contingencies (Details) R$ in Millions

3 Months Ended

12 Months Ended

Dec. 31, 2024 USD ($) claim

Dec. 31, 2024 USD ($) case claim

Jan. 17, 2025 company

Dec. 31, 2024 BRL (R$) claim

Sep. 30, 2024 USD ($)

Jul. 19, 2024 EUR (€)

Jul. 05, 2024 EUR (€)

Jun. 30, 2024 USD ($)

Dec. 31, 2023 USD ($)

Nov. 30, 2022 USD ($)

Feb. 25, 2022 EUR (€)

Oct. 14, 2021 EUR (€)

Dec. 30, 2020 USD ($)

Commitments and Contingencies

Proposed civil penalty

$ 800,000

Accrual for Environmental Loss Contingencies

$ 31,900,000

$ 31,900,000

Penalties per day | €

€ 5,000

€ 100,000

Malpractice Insurance, Deductible

$ 5,000,000

EnvironmentalLossContingencyStatementOfFinancialPositionExtensibleEnumerationNotDisclosedFlag

Company’s results of operations

Penalties

5,000,000

$ 5,000,000

R$ 32.0

Current Portion of Environmental Liabilities

$ 11,815,000

$ 11,815,000

$ 7,540,000

Subsequent Event

Commitments and Contingencies

Number Of Potentially Related Parties | company

30

Other

Commitments and Contingencies

Number of pending claims | claim

17,000

17,000

17,000

Loss provision

$ 0

Loss Contingency, Claims Dismissed, Number | case

28,500

Unfavorable Regulatory Action

Commitments and Contingencies

Loss provision

$ 27,200,000

Sao Paulo State Revenue Authority | Value-Added Tax Assessments January 2002 To December 2003

Commitments and Contingencies

Loss provision

$ 0

Brazil

Commitments and Contingencies

Loss Contingencies, Unpaid Service Taxes

$ 1,700,000

Loss Contingencies, Overall Liability

$ 5,600,000

$ 5,600,000

Kentucky Department of Environmental Protection

Commitments and Contingencies

Proposed civil penalty

$ 1,000,000

Current Portion of Environmental Liabilities

$ 200,000

Amsterdam Public Prosecutor’s Office | Alleged Violation of Environmental Permit in Ijmuiden, Netherland

Commitments and Contingencies

Loss Contingency, Fine Issued By Court | €

€ 25,000

€ 300,000

Capital Stock (Details)

Capital Stock (Details) - $ / shares	Dec. 31, 2024	Dec. 31, 2023
Equity [Abstract]
Common stock authorized (in shares)	150,000,000
Preferred stock authorized (in shares)	4,000,000
Common stock, par value (usd per share)	$ 1.25	$ 1.25
Preferred stock authorized, par value (in dollars per share)	$ 1.25
Preferred stock, shares issued (in shares)	0

Capital Stock (Details 2)

Capital Stock (Details 2) - shares	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Class of Stock [Line Items]
Common Stock, Shares, Issued	116,884,011	116,358,520	115,906,393
Treasury stock, beginning balance (in shares)	37,049,176	36,868,880	36,690,847
Common Stock, Shares, Outstanding, Beginning Balance	79,834,835	79,489,640	79,215,546
Vested Restricted Stock Units (in shares)	844	124,106	87,765
Stock issued during period, stock appreciation rights (in shares)			23,311
Shares outstanding at the end of the period	117,474,988	116,884,011	116,358,520
Treasury stock, ending balance (in shares)	37,277,211	37,049,176	36,868,880
Common Stock, Shares, Outstanding	80,197,777	79,834,835	79,489,640
Stock Issued During Period, Shares, Restricted Stock Award, Gross	590,133	401,385	341,051
Treasury
Class of Stock [Line Items]
Vested Restricted Stock Units (in shares)	241	57,637	40,304
Stock issued during period, stock appreciation rights (in shares)			6,640
Stock Issued During Period, Shares, Restricted Stock Award, Gross	227,794	122,659	131,089
Outstanding Shares
Class of Stock [Line Items]
Vested Restricted Stock Units (in shares)	603	66,469	47,461
Stock issued during period, stock appreciation rights (in shares)			16,671
Stock Issued During Period, Shares, Restricted Stock Award, Gross	362,339	278,726	209,962

Capital Stock - Reconciliation

Capital Stock - Reconciliation of the average shares of common stock used to compute basic earnings per common share to the shares used to compute diluted earnings per common share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Reconciliation of the average shares of common stock used to compute basic earnings per common share to the shares used to compute diluted earnings per common share
Income (loss) from continuing operations attributable to Harsco Corporation common stockholders (in dollars)	$ (124,058)	$ (82,320)	$ (176,569)
Weighted average shares of common stock outstanding	80,118	79,796	79,493
Dilutive effect of stock-based compensation (in shares)	0	0	0
Weighted-average shares outstanding—diluted (in shares)	80,118	79,796	79,493
Basic (in dollars per share)	$ (1.55)	$ (1.03)	$ (2.22)
Diluted (in dollars per share)	$ (1.55)	$ (1.03)	$ (2.22)

Capital Stock (Details 3)

Capital Stock (Details 3) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Restricted stock units
Antidilutive securities
Number of securities not included in computation of diluted earnings per share (in shares)	1,476	1,219	672
Stock Appreciation Rights (SARs)
Antidilutive securities
Number of securities not included in computation of diluted earnings per share (in shares)	2,618	2,303	2,092
Performance Shares [Member]
Antidilutive securities
Number of securities not included in computation of diluted earnings per share (in shares)	1,797	1,341	1,040

Stock-Based Compensation (Restr

Stock-Based Compensation (Restricted Stock) (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended				12 Months Ended
	Mar. 31, 2024	May 31, 2023	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)					767,699
Granted (in dollars per share)					$ 12.04
Restricted stock unit activity
Granted (in shares)					767,699
Vested (in shares)					(339,496)
Forfeited (in shares)					(79,071)
Weighted Average Grant-Date Fair Value
Granted (in dollars per share)					$ 12.04
Vested (in dollars per share)					16.54
Forfeited (in dollars per share)					$ 12.80
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)					905,624
Granted (in dollars per share)					$ 8.19
Recognized stock-based compensation expense					$ 6,338	$ 4,536	$ 4,522
Restricted stock unit activity
Nonvested at the beginning of the period (in shares)					1,219,321
Granted (in shares)					905,624
Vested (in shares)					(591,442)
Forfeited (in shares)					(57,847)
Nonvested at the end of the period (in shares)					1,475,656	1,219,321
Weighted Average Grant-Date Fair Value
Nonvested at the beginning of the period (in dollars per share)					$ 8.63
Granted (in dollars per share)					8.19
Vested (in dollars per share)					9.46
Forfeited (in dollars per share)					8.55
Nonvested at the end of the period (in dollars per share)					$ 8.01	$ 8.63
Additional disclosures
Unrecognized stock-based compensation expense					$ 6,800
Unrecognized stock-based compensation expense, period of recognition					1 year 9 months 18 days
Fair value of RSU, vested in period					$ 5,600	$ 4,100	5,100
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	778,702	29,337	758,965	500,624
Granted (in dollars per share)	$ 12.04	$ 15.24	$ 10.91	$ 16.54
Recognized stock-based compensation expense					$ 8,300	$ 5,900	$ 4,300
Restricted stock unit activity
Nonvested at the beginning of the period (in shares)					1,108,256
Granted (in shares)	778,702	29,337	758,965	500,624
Nonvested at the end of the period (in shares)					1,457,388	1,108,256
Weighted Average Grant-Date Fair Value
Nonvested at the beginning of the period (in dollars per share)					$ 12.87
Granted (in dollars per share)	$ 12.04	$ 15.24	$ 10.91	$ 16.54
Nonvested at the end of the period (in dollars per share)					$ 11.58	$ 12.87
Additional disclosures
Unrecognized stock-based compensation expense					$ 7,300
Unrecognized stock-based compensation expense, period of recognition					1 year 8 months 12 days
2013 Equity and Incentive Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares authorized for issuance					13,700,000
Number of shares available for grant					3,200,000
2013 Equity and Incentive Compensation Plan | Equity Awards, Other Than Options And Stock Appreciation Rights [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares authorized for issuance					9,700,000
Number of shares available for grant					2,300,000
1995 Non-Employee Directors' Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares authorized for issuance					800,000
Number of shares available for grant					101,000
1995 Non-Employee Directors' Stock Plan | Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)					80,125	80,705	63,696	23,224
Granted (in dollars per share)					$ 7.80	$ 9.03	$ 7.85	$ 21.53
Restricted stock unit activity
Granted (in shares)					80,125	80,705	63,696	23,224
Weighted Average Grant-Date Fair Value
Granted (in dollars per share)					$ 7.80	$ 9.03	$ 7.85	$ 21.53
1995 Non-Employee Directors' Stock Plan | Restricted stock units | 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized stock-based compensation expense					$ 0	$ 0	$ 167
1995 Non-Employee Directors' Stock Plan | Restricted stock units | 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized stock-based compensation expense					0	167	333
1995 Non-Employee Directors' Stock Plan | Restricted stock units | 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized stock-based compensation expense					213	516	0
1995 Non-Employee Directors' Stock Plan | Restricted stock units | 2024
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized stock-based compensation expense					$ 406	$ 0	$ 0
1995 Executive Incentive Compensation Plan | Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)					825,499	926,010	450,915	343,125	522,087	270,864
Granted (in dollars per share)					$ 8.22	$ 7.09	$ 12.36	$ 18.62	$ 8.22	$ 22.25
Restricted stock unit activity
Granted (in shares)					825,499	926,010	450,915	343,125	522,087	270,864
Weighted Average Grant-Date Fair Value
Granted (in dollars per share)					$ 8.22	$ 7.09	$ 12.36	$ 18.62	$ 8.22	$ 22.25
1995 Executive Incentive Compensation Plan | Restricted stock units | 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized stock-based compensation expense					$ 0	$ 0	$ 320
1995 Executive Incentive Compensation Plan | Restricted stock units | 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized stock-based compensation expense					0	90	800
1995 Executive Incentive Compensation Plan | Restricted stock units | 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized stock-based compensation expense					157	946	1,355
1995 Executive Incentive Compensation Plan | Restricted stock units | 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized stock-based compensation expense					1,035	1,095	1,547
1995 Executive Incentive Compensation Plan | Restricted stock units | 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized stock-based compensation expense					1,962	1,722	0
1995 Executive Incentive Compensation Plan | Restricted stock units | 2024
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized stock-based compensation expense					$ 2,565	$ 0	$ 0

Stock-Based Compensation (Stock

Stock-Based Compensation (Stock Appreciation Rights) (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended							12 Months Ended
	Mar. 31, 2024	May 31, 2023	Mar. 31, 2023	Dec. 31, 2022	Oct. 31, 2022	Sep. 30, 2022	Mar. 31, 2022	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Number of Shares
Stock appreciation rights exercised (in shares)								(603)		(16,671)
Weighted Average Exercise Price
Options vested, outstanding (in shares)								1,689,254
Options non-vested (in shares)								928,964
Weighted Average Exercise Price Per Share (in dollars per share)								$ 11.20
Weighted-Average Remaining Contractual Life in Years								5 years 5 months 23 days
Number of exercisable options (in shares)								1,689,254
Weighted average exercise price per share (in dollars per share)								$ 12.77
Unvested activity
Granted (in shares)								767,699
Vested (in shares)								(339,496)
Forfeited								(79,071)
Weighted Average Grant Date Fair Value
Granted (in dollars per share)								$ 12.04
Vested (in dollars per share)								16.54
Forfeited (in dollars per share)								$ 12.80
$5.02 - $13.70
Weighted Average Exercise Price
Options vested, outstanding (in shares)								1,103,357
Options non-vested (in shares)								928,964
Weighted Average Exercise Price Per Share (in dollars per share)								$ 9.07
Weighted-Average Remaining Contractual Life in Years								6 years 3 months 18 days
Number of exercisable options (in shares)								1,103,357
Weighted average exercise price per share (in dollars per share)								$ 9.69
$16.53 - $22.51
Weighted Average Exercise Price
Options vested, outstanding (in shares)								585,897
Options non-vested (in shares)								0
Weighted Average Exercise Price Per Share (in dollars per share)								$ 18.58
Weighted-Average Remaining Contractual Life in Years								2 years 7 months 24 days
Number of exercisable options (in shares)								585,897
Weighted average exercise price per share (in dollars per share)								$ 18.58
Stock Appreciation Rights (SARs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)								3 years
Expiration period (in years)								10 years
Fair value assumptions
Risk-free interest rate (as a percent)	4.04%	3.48%	4.20%	3.75%	4.10%	3.56%	1.67%
Dividend yield (as a percent)	0%	0%	0%	0%	0%	0%	0%
Expected life	6 years	6 years	6 years	6 years	6 years	6 years	6 years
Volatility (as a percent)	63.40%	63%	62.60%	62.40%	61.30%	60.60%	60.30%
SAR grant price (usd per share)	$ 8.20	$ 9.31	$ 7.45	$ 6.15	$ 5.26	$ 5.02	$ 12.65			$ 6.15
Number of Shares
Outstanding at beginning of period (in shares)								2,303,018
Granted (in shares)								567,967
Stock appreciation rights exercised (in shares)								(6,563)
Forfeited (in shares)								(246,204)
Outstanding at end of period (in shares)								2,618,218	2,303,018
Weighted Average Exercise Price
Outstanding at beginning of period (usd per share)								$ 13.01
Granted (usd per share)								8.20
Exercised (usd per share)								7.45
Forfeited/Expired (usd per share)								21.31
Outstanding at end of period								$ 11.20	$ 13.01
Outstanding - Aggregate Intrinsic Value								$ 400	$ 1,300
Total intrinsic value of SARs								0	0	$ 0
Recognized stock-based compensation expense								2,100	$ 1,500	1,500
Unrecognized stock-based compensation expense								$ 2,800
Unrecognized stock-based compensation expense, period of recognition								1 year 3 months 18 days
Unvested activity
Nonvested at the beginning of the period (in shares)								598,304
Granted (in shares)								567,967
Vested (in shares)								(220,327)
Forfeited								(16,980)
Nonvested at the end of the period (in shares)								928,964	598,304
Weighted Average Grant Date Fair Value
Nonvested at the beginning of the period (in dollars per share)								$ 5.51
Granted (in dollars per share)	$ 5.04	$ 5.64	$ 4.56	$ 3.72	$ 3.17	$ 2.97	$ 7.20	8.20
Vested (in dollars per share)								6.17
Forfeited (in dollars per share)								5.16
Nonvested at the end of the period (in dollars per share)								5.07	$ 5.51
Stock Appreciation Rights (SARs) | $5.02 - $13.70
Weighted Average Exercise Price
Range of Exercisable Prices, low end of range (in dollars per share)								5.02
Range of Exercisable Prices, high end of range (in dollars per share)								13.70
Stock Appreciation Rights (SARs) | $16.53 - $22.51
Weighted Average Exercise Price
Range of Exercisable Prices, low end of range (in dollars per share)								16.53
Range of Exercisable Prices, high end of range (in dollars per share)								$ 22.51
Performance Shares [Member]
Fair value assumptions
Risk-free interest rate (as a percent)	4.26%	3.75%	4.67%				1.59%
Dividend yield (as a percent)	0%	0%	0%				0%
Expected life	2 years 9 months 21 days	2 years 7 months 24 days	2 years 9 months 25 days				2 years 9 months 29 days
Weighted Average Exercise Price
Recognized stock-based compensation expense								$ 8,300	$ 5,900	4,300
Unrecognized stock-based compensation expense								$ 7,300
Unrecognized stock-based compensation expense, period of recognition								1 year 8 months 12 days
Unvested activity
Nonvested at the beginning of the period (in shares)								1,108,256
Granted (in shares)	778,702	29,337	758,965				500,624
Nonvested at the end of the period (in shares)								1,457,388	1,108,256
Weighted Average Grant Date Fair Value
Nonvested at the beginning of the period (in dollars per share)								$ 12.87
Granted (in dollars per share)	$ 12.04	$ 15.24	$ 10.91				$ 16.54
Nonvested at the end of the period (in dollars per share)								$ 11.58	$ 12.87
Performance period								3 years
Restricted stock units
Weighted Average Exercise Price
Recognized stock-based compensation expense								$ 6,338	$ 4,536	$ 4,522
Unrecognized stock-based compensation expense								$ 6,800
Unrecognized stock-based compensation expense, period of recognition								1 year 9 months 18 days
Unvested activity
Nonvested at the beginning of the period (in shares)								1,219,321
Granted (in shares)								905,624
Vested (in shares)								(591,442)
Forfeited								(57,847)
Nonvested at the end of the period (in shares)								1,475,656	1,219,321
Weighted Average Grant Date Fair Value
Nonvested at the beginning of the period (in dollars per share)								$ 8.63
Granted (in dollars per share)								8.19
Vested (in dollars per share)								9.46
Forfeited (in dollars per share)								8.55
Nonvested at the end of the period (in dollars per share)								$ 8.01	$ 8.63
Restricted stock units | Non-employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)								1 year
Restricted stock units | Officers And Key Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)								3 years
2013 Equity and Incentive Compensation Plan | Stock Appreciation Rights (SARs)
Unvested activity
Granted (in shares)	567,967	48,427	404,594	10,000	10,000	10,000	312,987

Stock-Based Compensation (Perfo

Stock-Based Compensation (Performance Stock Units) (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended				12 Months Ended
	Mar. 31, 2024	May 31, 2023	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Fair value assumptions
Fair value of award (in dollars per share)					$ 12.04
Unvested activity
Granted (in shares)					767,699
Forfeited (in shares)					(79,071)
Vested (in shares)					(339,496)
Weighted Average Grant Date Fair Value
Granted (in dollars per share)					$ 12.04
Forfeited (in dollars per share)					12.80
Vested (in dollars per share)					$ 16.54
Performance Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period					3 years
Fair value assumptions
Risk-free interest rate (as a percent)	4.26%	3.75%	4.67%	1.59%
Dividend yield (as a percent)	0%	0%	0%	0%
Expected Life (Years)	2 years 9 months 21 days	2 years 7 months 24 days	2 years 9 months 25 days	2 years 9 months 29 days
Volatility	39.80%	41.50%	43.90%	50.40%
Fair value of award (in dollars per share)	$ 12.04	$ 15.24	$ 10.91	$ 16.54
Recognized stock-based compensation expense					$ 8.3	$ 5.9	$ 4.3
Unrecognized stock-based compensation expense					$ 7.3
Unrecognized stock-based compensation expense, period of recognition					1 year 8 months 12 days
Unvested activity
Nonvested at the beginning of the period (in shares)					1,108,256
Granted (in shares)	778,702	29,337	758,965	500,624
Nonvested at the end of the period (in shares)					1,457,388	1,108,256
Weighted Average Grant Date Fair Value
Nonvested at the beginning of the period (in dollars per share)					$ 12.87
Granted (in dollars per share)	$ 12.04	$ 15.24	$ 10.91	$ 16.54
Nonvested at the end of the period (in dollars per share)					$ 11.58	$ 12.87
Shares expected to be issued (in shares)					0
Performance Stock Units | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout of PSUs (percent of initial grant)					0%
Performance Stock Units | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout of PSUs (percent of initial grant)					200%

Stock-Based Compensation - Othe

Stock-Based Compensation - Other Stock Grants (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Aug. 31, 2022
Share-Based Payment Arrangement [Abstract]
Stock, Common Stock, Compensation, Value			$ 0.1
Stock Issued During Period, Shares, New Issues	124,106	87,765
Compensation Arrangement with Individual, Compensation Expense	$ 0.9	$ 0.5

Financial Instruments - Narrati

Financial Instruments - Narrative (Details)	12 Months Ended
	Dec. 31, 2024 USD ($) country	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Oct. 31, 2024 USD ($)	Mar. 31, 2023 USD ($)
Guarantor Obligations [Line Items]
Derivatives liability resulted from netting arrangement	$ 2,200,000	$ (500,000)
Pre-tax gains (losses)	2,400,000	1,100,000	$ (2,600,000)
Fair value of long-term debt	1,419,700,000	1,394,500,000
Long-term Debt, Gross	1,444,417,000	1,428,969,000
Foreign currency exchange forward contracts
Guarantor Obligations [Line Items]
Notional amounts	$ 593,700,000	633,300,000
Interest rate swaps
Guarantor Obligations [Line Items]
Notional amounts				$ 300,000,000	$ 300,000,000
Minimum
Guarantor Obligations [Line Items]
Number of countries in which entity has currency exposures | country	30
Minimum | Interest rate swaps
Guarantor Obligations [Line Items]
Derivative, Fixed Interest Rate				3.06%	4.16%
Maximum | Interest rate swaps
Guarantor Obligations [Line Items]
Derivative, Fixed Interest Rate				3.12%	4.21%
Stand by letters of credit, bonds and bank guarantees
Guarantor Obligations [Line Items]
Contingent liability outstanding	$ 451,800,000	$ 489,600,000	$ 500,400,000
Guarantee term	2 years
Stand by letters of credit, bonds and bank guarantees | Minimum
Guarantor Obligations [Line Items]
Guarantee term	1 year
Fees paid to various banks and insurance companies on face amount of instruments (as a percent)	0.20%
Stand by letters of credit, bonds and bank guarantees | Maximum
Guarantor Obligations [Line Items]
Guarantee term	10 years
Fees paid to various banks and insurance companies on face amount of instruments (as a percent)	3%
Indemnification Agreement
Guarantor Obligations [Line Items]
Recognition of potential future payment in the consolidated financial statements	$ 0

Financial Instruments - Fair Va

Financial Instruments - Fair Value of Outstanding Derivative Contracts Recorded as Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Derivatives, Fair Value [Line Items]
Asset derivatives (Level 2):	$ 13,187	$ 3,117
Liability derivatives (Level 2)	1,284	10,775
Foreign currency exchange forward contracts | Other current assets
Derivatives, Fair Value [Line Items]
Asset derivatives (Level 2):	7,937	1,674
Foreign currency exchange forward contracts | Other current liabilities
Derivatives, Fair Value [Line Items]
Liability derivatives (Level 2)	1,067	8,625
Interest rate swaps | Other current assets
Derivatives, Fair Value [Line Items]
Asset derivatives (Level 2):		1,443
Interest rate swaps | Other assets
Derivatives, Fair Value [Line Items]
Asset derivatives (Level 2):	5,250
Interest rate swaps | Other current liabilities
Derivatives, Fair Value [Line Items]
Liability derivatives (Level 2)	217
Interest rate swaps | Other liabilities
Derivatives, Fair Value [Line Items]
Liability derivatives (Level 2)		2,150
Fair Value of Derivatives Designated as Hedging Instruments
Derivatives, Fair Value [Line Items]
Asset derivatives (Level 2):	5,597	1,520
Liability derivatives (Level 2)	297	2,711
Fair Value of Derivatives Designated as Hedging Instruments | Foreign currency exchange forward contracts | Other current assets
Derivatives, Fair Value [Line Items]
Asset derivatives (Level 2):	347	77
Fair Value of Derivatives Designated as Hedging Instruments | Foreign currency exchange forward contracts | Other current liabilities
Derivatives, Fair Value [Line Items]
Liability derivatives (Level 2)	80	561
Fair Value of Derivatives Designated as Hedging Instruments | Interest rate swaps | Other current assets
Derivatives, Fair Value [Line Items]
Asset derivatives (Level 2):		1,443
Fair Value of Derivatives Designated as Hedging Instruments | Interest rate swaps | Other assets
Derivatives, Fair Value [Line Items]
Asset derivatives (Level 2):	5,250
Fair Value of Derivatives Designated as Hedging Instruments | Interest rate swaps | Other current liabilities
Derivatives, Fair Value [Line Items]
Liability derivatives (Level 2)	217
Fair Value of Derivatives Designated as Hedging Instruments | Interest rate swaps | Other liabilities
Derivatives, Fair Value [Line Items]
Liability derivatives (Level 2)		2,150
Fair Value of Derivatives Not Designated as Hedging Instruments
Derivatives, Fair Value [Line Items]
Asset derivatives (Level 2):	7,590	1,597
Liability derivatives (Level 2)	987	8,064
Fair Value of Derivatives Not Designated as Hedging Instruments | Foreign currency exchange forward contracts | Other current assets
Derivatives, Fair Value [Line Items]
Asset derivatives (Level 2):	7,590	1,597
Fair Value of Derivatives Not Designated as Hedging Instruments | Foreign currency exchange forward contracts | Other current liabilities
Derivatives, Fair Value [Line Items]
Liability derivatives (Level 2)	987	8,064
Fair Value of Derivatives Not Designated as Hedging Instruments | Interest rate swaps | Other current assets
Derivatives, Fair Value [Line Items]
Asset derivatives (Level 2):		0
Fair Value of Derivatives Not Designated as Hedging Instruments | Interest rate swaps | Other assets
Derivatives, Fair Value [Line Items]
Asset derivatives (Level 2):	0
Fair Value of Derivatives Not Designated as Hedging Instruments | Interest rate swaps | Other current liabilities
Derivatives, Fair Value [Line Items]
Liability derivatives (Level 2)	$ 0
Fair Value of Derivatives Not Designated as Hedging Instruments | Interest rate swaps | Other liabilities
Derivatives, Fair Value [Line Items]
Liability derivatives (Level 2)		$ 0

Financial Instruments - Effect

Financial Instruments - Effect of Derivative Instruments on the Consolidated Statements of Operations and the Consolidated Statements of Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Derivative Instruments, Gain (Loss) [Line Items]
Interest expense	$ (112,217)	$ (107,081)	$ (76,807)
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax	(3,713)	(938)	(2,499)
Foreign currency exchange forward contracts | Product revenues / Cost of services and products sold
Derivative Not Designated as Hedging Instruments
Amount of Gain (Loss) Recognized in Income on Derivative for the Twelve Months Ended December 31	25,184	426	19,808
Interest rate swaps | Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax	0	0	0
Interest rate swaps | Interest expense
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax	3,018	2,576	(4,245)
Gain (Loss) on Discontinuation of Cash Flow Hedge Due to Forecasted Transaction Probable of Not Occurring, Net			1,862
Foreign Exchange Contract [Member] | Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax	(695)	(1,638)	1,746
Foreign Exchange Contract [Member] | Interest expense
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax	$ 0	$ 0	$ 0

Financial Instruments - Effec_2

Financial Instruments - Effect of Derivatives (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Derivatives, Fair Value [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax	$ 9,349	$ 173
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax			$ 1,966
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax	3,713	938	2,499
Foreign Exchange Forward Two [Member]
Derivatives, Fair Value [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax	592	(1,696)
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax			1,966
Interest Rate Swap Two [Member]
Derivatives, Fair Value [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax	8,757	1,869
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax			0
Interest expense | Interest rate swaps
Derivatives, Fair Value [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax	(3,018)	(2,576)	4,245
Discontinued Operations, Held-for-sale or Disposed of by Sale | Foreign currency exchange forward contracts
Derivatives, Fair Value [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax	$ 695	$ (1,638)	$ (1,746)

Information by Segment and Ge_3

Information by Segment and Geographic Area (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2024 USD ($) segment	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Revenue, Major Customer [Line Items]
Revenues	$ 2,342,645	$ 2,366,020	$ 2,133,981
Number of reportable segments | segment	3
All Other
Revenue, Major Customer [Line Items]
Revenues	$ 1,001,850	959,758	894,636
U.S. Plans
Revenue, Major Customer [Line Items]
Revenues	$ 1,340,795	$ 1,406,262	$ 1,239,345

Information by Segment and Ge_4

Information by Segment and Geographic Area (Details 2) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Revenues from External Customers and Long-Lived Assets [Line Items]
Property, plant and equipment, net	$ 664,292	$ 707,397
Percent of Revenue , Unaffiliated Customer	10%
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Property, plant and equipment, net	$ 338,679	339,231
All Other
Revenues from External Customers and Long-Lived Assets [Line Items]
Property, plant and equipment, net	$ 325,613	$ 368,166

Information by Segment and Ge_5

Information by Segment and Geographic Area (Details 3) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Segment Reporting Information [Line Items]
Total revenues	$ 2,342,645	$ 2,366,020	$ 2,133,981
Cost of services and products sold			1,799,483
Selling, general and administrative costs	359,388	353,985	304,865
Goodwill and other intangible asset impairment charges	15,866	0	119,580
Other segment activities	2,904	3,211	10,949
Property, plant and equipment impairment charge	23,444	14,099	0
Remeasurement of long-lived assets	10,695	0	0
Gain (Loss) on Disposition of Business	(10,478)	0	0
Other Operating Income (Expense), Net	(5,437)	1,591	(11,654)
Operating income from continuing operations	31,745	79,938	(100,896)
Interest income	6,795	6,809	3,829
Interest expense	(112,217)	(107,081)	(76,807)
Loss on early extinguishment of debt	(11,265)	(10,762)	(2,956)
Defined benefit pension income (expense)	(16,728)	(21,574)	8,933
Income (loss) from continuing operations before income taxes and equity income	(101,670)	(52,670)	(167,897)
Depreciation	148,329	138,956	129,712
Amortization	31,471	32,408	34,137
Capital expenditures	136,591	139,025	137,160
Total assets	2,650,233	2,854,698
Service and Product
Segment Reporting Information [Line Items]
Cost of services and products sold	1,909,081	1,914,787
Operating segments
Segment Reporting Information [Line Items]
Total revenues	2,342,645	2,366,020	2,133,981
Cost of services and products sold			1,799,483
Selling, general and administrative costs	318,684	309,414	270,223
Goodwill and other intangible asset impairment charges	15,866		119,580
Other segment activities	8,767	4,782	10,602
Property, plant and equipment impairment charge	23,444	14,099
Remeasurement of long-lived assets	10,695
Gain (Loss) on Disposition of Business	(10,029)
Operating income from continuing operations	66,137	122,938	(65,907)
Depreciation	147,074	136,823	127,716
Amortization	27,268	28,613	31,108
Capital expenditures	136,355	138,598	133,122
Total assets	2,606,786	2,768,023
Operating segments | Service and Product
Segment Reporting Information [Line Items]
Cost of services and products sold	1,909,081	1,914,787
Operating segments | Harsco Environmental
Segment Reporting Information [Line Items]
Total revenues	1,111,512	1,140,904	1,061,239
Cost of services and products sold			881,249
Selling, general and administrative costs	113,845	109,131	99,855
Goodwill and other intangible asset impairment charges	2,840		15,000
Other segment activities	808	(2,180)	5,576
Property, plant and equipment impairment charge	23,444	14,099
Remeasurement of long-lived assets	0
Gain (Loss) on Disposition of Business	(10,029)
Operating income from continuing operations	32,013	77,635	59,559
Depreciation	109,756	113,571	108,880
Amortization	3,068	4,030	6,809
Capital expenditures	98,845	104,045	109,508
Total assets	1,263,031	1,417,278
Operating segments | Harsco Environmental | Service and Product
Segment Reporting Information [Line Items]
Cost of services and products sold	948,591	942,219
Operating segments | Clean Earth
Segment Reporting Information [Line Items]
Total revenues	939,845	928,321	827,826
Cost of services and products sold			675,283
Selling, general and administrative costs	156,378	154,513	129,401
Goodwill and other intangible asset impairment charges	0		104,580
Other segment activities	1,151	2,078	347
Property, plant and equipment impairment charge	0	0
Remeasurement of long-lived assets	0
Gain (Loss) on Disposition of Business	0
Operating income from continuing operations	92,156	76,974	(81,785)
Depreciation	33,840	23,252	18,836
Amortization	23,976	24,583	24,299
Capital expenditures	32,754	32,100	21,996
Total assets	993,598	981,723
Operating segments | Clean Earth | Service and Product
Segment Reporting Information [Line Items]
Cost of services and products sold	690,160	694,756
Operating segments | Harsco Rail
Segment Reporting Information [Line Items]
Total revenues	291,288	296,795	244,916
Cost of services and products sold			242,951
Selling, general and administrative costs	48,461	45,770	40,967
Goodwill and other intangible asset impairment charges	13,026		0
Other segment activities	6,808	4,884	4,679
Property, plant and equipment impairment charge	0	0
Remeasurement of long-lived assets	10,695
Gain (Loss) on Disposition of Business	0
Operating income from continuing operations	(58,032)	(31,671)	(43,681)
Depreciation	3,478	0	0
Amortization	224	0	0
Capital expenditures	4,756	2,453	1,618
Total assets	350,157	369,022
Operating segments | Harsco Rail | Service and Product
Segment Reporting Information [Line Items]
Cost of services and products sold	270,330	277,812
Corporate
Segment Reporting Information [Line Items]
Total revenues	0	0	0
Cost of services and products sold			0
Selling, general and administrative costs	40,704	44,571	34,642
Goodwill and other intangible asset impairment charges	0		0
Other segment activities	(5,863)	(1,571)	347
Property, plant and equipment impairment charge	0	0
Remeasurement of long-lived assets	0
Gain (Loss) on Disposition of Business	(449)
Operating income from continuing operations	(34,392)	(43,000)	(34,989)
Depreciation	1,255	2,133	1,996
Amortization	4,203	3,795	3,029
Capital expenditures	236	427	$ 4,038
Total assets	43,447	86,675
Corporate | Service and Product
Segment Reporting Information [Line Items]
Cost of services and products sold	$ 0	$ 0

Revenue Recognition - Summary o

Revenue Recognition - Summary of Revenues by Primary Geographical Markets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Disaggregation of Revenue [Line Items]
Total revenues	$ 2,342,645	$ 2,366,020	$ 2,133,981
Environmental services related to resource recovery for metals manufacturing; and related logistical services
Disaggregation of Revenue [Line Items]
Total revenues	967,188	950,961	900,426
Applied Products [Member]
Disaggregation of Revenue [Line Items]
Total revenues	120,896	162,291	145,911
Aluminum Dross and Scrap Processing Systems [Member]
Disaggregation of Revenue [Line Items]
Total revenues	23,428	27,652	14,902
Railway Track Maintenance Equipment
Disaggregation of Revenue [Line Items]
Total revenues	113,039	128,155	100,032
After Market Parts and Services; Safety and Diagnostic Technology
Disaggregation of Revenue [Line Items]
Total revenues	117,327	121,039	118,829
Railway Contracting Services
Disaggregation of Revenue [Line Items]
Total revenues	60,922	47,601	26,055
Soil and dredged material
Disaggregation of Revenue [Line Items]
Total revenues	161,443	160,983	146,022
Waste Processing and Reuse Solutions [Member]
Disaggregation of Revenue [Line Items]
Total revenues	778,402	767,338	681,804
North America
Disaggregation of Revenue [Line Items]
Total revenues	1,405,543	1,461,788	1,289,368
Western Europe
Disaggregation of Revenue [Line Items]
Total revenues	510,173	489,194	435,220
Latin America
Disaggregation of Revenue [Line Items]
Total revenues	160,262	172,734	156,791
Asia-Pacific
Disaggregation of Revenue [Line Items]
Total revenues	145,411	135,861	153,288
Middle East and Africa
Disaggregation of Revenue [Line Items]
Total revenues	103,957	86,867	79,562
Eastern Europe
Disaggregation of Revenue [Line Items]
Total revenues	17,299	19,576	19,752
Operating segments
Disaggregation of Revenue [Line Items]
Total revenues	2,342,645	2,366,020	2,133,981
Corporate
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0
Harsco Environmental | Operating segments
Disaggregation of Revenue [Line Items]
Total revenues	1,111,512	1,140,904	1,061,239
Harsco Environmental | Operating segments | Environmental services related to resource recovery for metals manufacturing; and related logistical services
Disaggregation of Revenue [Line Items]
Total revenues	967,188	950,961	900,426
Harsco Environmental | Operating segments | Applied Products [Member]
Disaggregation of Revenue [Line Items]
Total revenues	120,896	162,291	145,911
Harsco Environmental | Operating segments | Aluminum Dross and Scrap Processing Systems [Member]
Disaggregation of Revenue [Line Items]
Total revenues	23,428	27,652	14,902
Harsco Environmental | Operating segments | Railway Track Maintenance Equipment
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0
Harsco Environmental | Operating segments | After Market Parts and Services; Safety and Diagnostic Technology
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0
Harsco Environmental | Operating segments | Railway Contracting Services
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0
Harsco Environmental | Operating segments | Soil and dredged material
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0
Harsco Environmental | Operating segments | Waste Processing and Reuse Solutions [Member]
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0
Harsco Environmental | Operating segments | North America
Disaggregation of Revenue [Line Items]
Total revenues	292,274	318,574	297,544
Harsco Environmental | Operating segments | Western Europe
Disaggregation of Revenue [Line Items]
Total revenues	425,775	431,893	389,713
Harsco Environmental | Operating segments | Latin America
Disaggregation of Revenue [Line Items]
Total revenues	154,684	170,194	155,235
Harsco Environmental | Operating segments | Asia-Pacific
Disaggregation of Revenue [Line Items]
Total revenues	117,523	113,800	119,433
Harsco Environmental | Operating segments | Middle East and Africa
Disaggregation of Revenue [Line Items]
Total revenues	103,957	86,867	79,562
Harsco Environmental | Operating segments | Eastern Europe
Disaggregation of Revenue [Line Items]
Total revenues	17,299	19,576	19,752
Clean Earth | Operating segments
Disaggregation of Revenue [Line Items]
Total revenues	939,845	928,321	827,826
Clean Earth | Operating segments | Environmental services related to resource recovery for metals manufacturing; and related logistical services
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0
Clean Earth | Operating segments | Applied Products [Member]
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0
Clean Earth | Operating segments | Aluminum Dross and Scrap Processing Systems [Member]
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0
Clean Earth | Operating segments | Railway Track Maintenance Equipment
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0
Clean Earth | Operating segments | After Market Parts and Services; Safety and Diagnostic Technology
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0
Clean Earth | Operating segments | Railway Contracting Services
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0
Clean Earth | Operating segments | Soil and dredged material
Disaggregation of Revenue [Line Items]
Total revenues	161,443	160,983	146,022
Clean Earth | Operating segments | Waste Processing and Reuse Solutions [Member]
Disaggregation of Revenue [Line Items]
Total revenues	778,402	767,338	681,804
Clean Earth | Operating segments | North America
Disaggregation of Revenue [Line Items]
Total revenues	939,845	928,321	827,826
Clean Earth | Operating segments | Western Europe
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0
Clean Earth | Operating segments | Latin America
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0
Clean Earth | Operating segments | Asia-Pacific
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0
Clean Earth | Operating segments | Middle East and Africa
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0
Clean Earth | Operating segments | Eastern Europe
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0
Harsco Rail | Operating segments
Disaggregation of Revenue [Line Items]
Total revenues	291,288	296,795	244,916
Harsco Rail | Operating segments | Environmental services related to resource recovery for metals manufacturing; and related logistical services
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0
Harsco Rail | Operating segments | Applied Products [Member]
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0
Harsco Rail | Operating segments | Aluminum Dross and Scrap Processing Systems [Member]
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0
Harsco Rail | Operating segments | Railway Track Maintenance Equipment
Disaggregation of Revenue [Line Items]
Total revenues	113,039	128,155	100,032
Harsco Rail | Operating segments | After Market Parts and Services; Safety and Diagnostic Technology
Disaggregation of Revenue [Line Items]
Total revenues	117,327	121,039	118,829
Harsco Rail | Operating segments | Railway Contracting Services
Disaggregation of Revenue [Line Items]
Total revenues	60,922	47,601	26,055
Harsco Rail | Operating segments | Soil and dredged material
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0
Harsco Rail | Operating segments | Waste Processing and Reuse Solutions [Member]
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0
Harsco Rail | Operating segments | North America
Disaggregation of Revenue [Line Items]
Total revenues	173,424	214,893	163,998
Harsco Rail | Operating segments | Western Europe
Disaggregation of Revenue [Line Items]
Total revenues	84,398	57,301	45,507
Harsco Rail | Operating segments | Latin America
Disaggregation of Revenue [Line Items]
Total revenues	5,578	2,540	1,556
Harsco Rail | Operating segments | Asia-Pacific
Disaggregation of Revenue [Line Items]
Total revenues	27,888	22,061	33,855
Harsco Rail | Operating segments | Middle East and Africa
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0
Harsco Rail | Operating segments | Eastern Europe
Disaggregation of Revenue [Line Items]
Total revenues	$ 0	$ 0	$ 0

Revenue Recognition - Performan

Revenue Recognition - Performance Obligation Period Narrative (Details) - Harsco Rail $ in Thousands	Dec. 31, 2024 USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 105,823
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance period	1 year
Remaining performance obligation	$ 51,037
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance period	1 year
Remaining performance obligation	$ 24,980
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance period	1 year
Remaining performance obligation	$ 17,955
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance period	1 year
Remaining performance obligation	$ 5,137
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2029-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance period	1 year
Remaining performance obligation	$ 4,038
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2030-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance period
Remaining performance obligation	$ 2,676

Revenue Recognition - Narrative

Revenue Recognition - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Revenue from Contract with Customer [Abstract]
Total contract assets	$ 97,200	$ 97,200	$ 86,900
Revenue recognized in excess of amounts reclassified to trade accounts receivable, net	23,900	23,900	38,600
Contract with Customer, Liability, Revenue Recognized		32,700
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		2,342,645	2,366,020	$ 2,133,981
Contract estimated forward loss provision for Harsco Rail Segment		32,700	32,800	44,500
Deutsche Bahn
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Contract estimated forward loss provision for Harsco Rail Segment	$ 7,200	$ 14,400	39,900
Percentage Complete	48%	48%
SBB
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Contract estimated forward loss provision for Harsco Rail Segment			7,300
Percentage Complete	91%	91%
Increase (Decrease) To Loss On Contracts	$ 2,700	$ 2,200
Network Rail
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Contract estimated forward loss provision for Harsco Rail Segment	$ 2,800	$ 16,100	14,400
Network Rail | Contract 2
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Percentage Complete	64%	64%
North America
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		$ 1,405,543	1,461,788	1,289,368
Western Europe
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		510,173	489,194	435,220
Latin America
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		160,262	172,734	156,791
Asia-Pacific
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		145,411	135,861	153,288
Middle East and Africa
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		103,957	86,867	79,562
Eastern Europe
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		17,299	19,576	19,752
Waste Processing and Reuse Solutions [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		778,402	767,338	681,804
Aluminum Dross and Scrap Processing Systems [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		23,428	27,652	14,902
Environmental services related to resource recovery for metals manufacturing; and related logistical services
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		967,188	950,961	900,426
Applied Products [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		120,896	162,291	145,911
Soil and dredged material
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		161,443	160,983	146,022
After Market Parts and Services; Safety and Diagnostic Technology
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		117,327	121,039	118,829
Railway Track Maintenance Equipment
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		113,039	128,155	100,032
Railway Contracting Services
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		60,922	47,601	26,055
Operating Segments [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		2,342,645	2,366,020	2,133,981
Operating Segments [Member] | Clean Earth
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		939,845	928,321	827,826
Operating Segments [Member] | Clean Earth | North America
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		939,845	928,321	827,826
Operating Segments [Member] | Clean Earth | Western Europe
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		0	0	0
Operating Segments [Member] | Clean Earth | Latin America
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		0	0	0
Operating Segments [Member] | Clean Earth | Asia-Pacific
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		0	0	0
Operating Segments [Member] | Clean Earth | Middle East and Africa
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		0	0	0
Operating Segments [Member] | Clean Earth | Eastern Europe
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		0	0	0
Operating Segments [Member] | Harsco Environmental
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		1,111,512	1,140,904	1,061,239
Operating Segments [Member] | Harsco Environmental | North America
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		292,274	318,574	297,544
Operating Segments [Member] | Harsco Environmental | Western Europe
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		425,775	431,893	389,713
Operating Segments [Member] | Harsco Environmental | Latin America
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		154,684	170,194	155,235
Operating Segments [Member] | Harsco Environmental | Asia-Pacific
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		117,523	113,800	119,433
Operating Segments [Member] | Harsco Environmental | Middle East and Africa
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		103,957	86,867	79,562
Operating Segments [Member] | Harsco Environmental | Eastern Europe
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		17,299	19,576	19,752
Operating Segments [Member] | Harsco Rail
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		291,288	296,795	244,916
Operating Segments [Member] | Harsco Rail | North America
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		173,424	214,893	163,998
Operating Segments [Member] | Harsco Rail | Western Europe
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		84,398	57,301	45,507
Operating Segments [Member] | Harsco Rail | Latin America
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		5,578	2,540	1,556
Operating Segments [Member] | Harsco Rail | Asia-Pacific
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		27,888	22,061	33,855
Operating Segments [Member] | Harsco Rail | Middle East and Africa
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		0	0	0
Operating Segments [Member] | Harsco Rail | Eastern Europe
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		0	0	0
Operating Segments [Member] | Waste Processing and Reuse Solutions [Member] | Clean Earth
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		778,402	767,338	681,804
Operating Segments [Member] | Waste Processing and Reuse Solutions [Member] | Harsco Environmental
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		0	0	0
Operating Segments [Member] | Waste Processing and Reuse Solutions [Member] | Harsco Rail
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		0	0	0
Operating Segments [Member] | Aluminum Dross and Scrap Processing Systems [Member] | Clean Earth
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		0	0	0
Operating Segments [Member] | Aluminum Dross and Scrap Processing Systems [Member] | Harsco Environmental
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		23,428	27,652	14,902
Operating Segments [Member] | Aluminum Dross and Scrap Processing Systems [Member] | Harsco Rail
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		0	0	0
Operating Segments [Member] | Environmental services related to resource recovery for metals manufacturing; and related logistical services | Clean Earth
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		0	0	0
Operating Segments [Member] | Environmental services related to resource recovery for metals manufacturing; and related logistical services | Harsco Environmental
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		967,188	950,961	900,426
Operating Segments [Member] | Environmental services related to resource recovery for metals manufacturing; and related logistical services | Harsco Rail
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		0	0	0
Operating Segments [Member] | Applied Products [Member] | Clean Earth
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		0	0	0
Operating Segments [Member] | Applied Products [Member] | Harsco Environmental
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		120,896	162,291	145,911
Operating Segments [Member] | Applied Products [Member] | Harsco Rail
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		0	0	0
Operating Segments [Member] | Soil and dredged material | Clean Earth
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		161,443	160,983	146,022
Operating Segments [Member] | Soil and dredged material | Harsco Environmental
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		0	0	0
Operating Segments [Member] | Soil and dredged material | Harsco Rail
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		0	0	0
Operating Segments [Member] | After Market Parts and Services; Safety and Diagnostic Technology | Clean Earth
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		0	0	0
Operating Segments [Member] | After Market Parts and Services; Safety and Diagnostic Technology | Harsco Environmental
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		0	0	0
Operating Segments [Member] | After Market Parts and Services; Safety and Diagnostic Technology | Harsco Rail
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		117,327	121,039	118,829
Operating Segments [Member] | Railway Track Maintenance Equipment | Clean Earth
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		0	0	0
Operating Segments [Member] | Railway Track Maintenance Equipment | Harsco Environmental
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		0	0	0
Operating Segments [Member] | Railway Track Maintenance Equipment | Harsco Rail
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		113,039	128,155	100,032
Operating Segments [Member] | Railway Contracting Services | Clean Earth
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		0	0	0
Operating Segments [Member] | Railway Contracting Services | Harsco Environmental
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		0	0	0
Operating Segments [Member] | Railway Contracting Services | Harsco Rail
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		60,922	47,601	26,055
Corporate
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total revenues		$ 0	$ 0	$ 0

Revenue Recognition - Schedule

Revenue Recognition - Schedule of Performance Obligation (Details) $ in Thousands	Dec. 31, 2024 USD ($)
Harsco Environmental
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 62,574
Harsco Rail
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	105,823
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01 | Harsco Environmental
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 17,019
Performance period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01 | Harsco Rail
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 51,037
Performance period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01 | Harsco Environmental
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 15,367
Performance period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01 | Harsco Rail
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 24,980
Performance period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01 | Harsco Environmental
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 12,803
Performance period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01 | Harsco Rail
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 17,955
Performance period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01 | Harsco Environmental
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 11,121
Performance period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01 | Harsco Rail
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 5,137
Performance period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2029-01-01 | Harsco Environmental
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 3,132
Performance period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2029-01-01 | Harsco Rail
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 4,038
Performance period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2030-01-01 | Harsco Environmental
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 3,132
Performance period
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2030-01-01 | Harsco Rail
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 2,676
Performance period

Other Expenses (Details)

Other Expenses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Segment Reporting Information [Line Items]
Net gains	$ (6,629)	$ (2,561)	$ (4,013)
Employee termination benefit costs	8,353	3,006	8,215
Costs to exit activities	(1,546)	(1,565)	5,449
Impaired asset write-downs	5,259	88	736
Contingent Consideration Adjustments	0	(848)	(827)
Other expense	0	289	2,094
Total	5,437	(1,591)	11,654
Gain (Loss) on Disposition of Business	(10,478)	0	0
Business Exit Costs (Gain)		(8,100)
Corporate
Segment Reporting Information [Line Items]
Net gains	(3,272)	0	(632)
Employee termination benefit costs	1,179	275	(294)
Costs to exit activities	2,060	2,669	1,407
Contingent Consideration Adjustments	0	(848)	0
Harsco Environmental
Segment Reporting Information [Line Items]
Net gains	(3,357)	(250)	(1,869)
Employee termination benefit costs	6,013	1,977	4,998
Costs to exit activities	(3,615)	(7,810)	39
Impaired asset write-downs	2,771	88	582
Clean Earth
Segment Reporting Information [Line Items]
Net gains	0	0	(1,512)
Employee termination benefit costs	521	1,399	1,786
Costs to exit activities	0	0	0
Impaired asset write-downs	567	0	59
Contingent Consideration Adjustments	0	0	(827)
Harsco Rail
Segment Reporting Information [Line Items]
Net gains	0	(2,311)	0
Employee termination benefit costs	640	(645)	1,725
Costs to exit activities	9	3,576	4,003
Impaired asset write-downs	$ 1,921	$ 0	$ 95

Components of Accumulated Oth_3

Components of Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balances	$ 575,408	$ 623,042	$ 805,770
OCI before reclassifications	(15,140)	10,298
Amounts reclassified from AOCI, net of tax	14,645	17,027
Other Comprehensive Income (Loss), Net of Tax, Total	(495)	27,325	(11,607)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Noncontrolling Interest	1,225	617
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent, Total	730	27,942
Balances	449,599	575,408	623,042
Cumulative Effect, Period of Adoption, Adjusted Balance
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balances		(567,636)
Balances			(567,636)
Accumulated Foreign Currency Adjustment Attributable to Parent
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balances	(183,499)
OCI before reclassifications	(46,316)	29,495
Amounts reclassified from AOCI, net of tax	(108)	(507)
Other Comprehensive Income (Loss), Net of Tax, Total	(46,424)	28,988
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Noncontrolling Interest	1,225	617
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent, Total	(45,199)	29,605
Balances	(228,698)	(183,499)
Accumulated Foreign Currency Adjustment Attributable to Parent | Cumulative Effect, Period of Adoption, Adjusted Balance
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balances		(213,104)
Balances			(213,104)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balances	(470)
OCI before reclassifications	7,036	64
Amounts reclassified from AOCI, net of tax	(2,797)	(691)
Other Comprehensive Income (Loss), Net of Tax, Total	4,239	(627)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Noncontrolling Interest	0	0
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent, Total	4,239	(627)
Balances	3,769	(470)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent | Cumulative Effect, Period of Adoption, Adjusted Balance
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balances		157
Balances			157
Accumulated Defined Benefit Plans Adjustment Attributable to Parent
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balances	(355,740)
OCI before reclassifications	24,133	(19,266)
Amounts reclassified from AOCI, net of tax	17,550	18,225
Other Comprehensive Income (Loss), Net of Tax, Total	41,683	(1,041)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Noncontrolling Interest	0	0
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent, Total	41,683	(1,041)
Balances	(314,057)	(355,740)
Accumulated Defined Benefit Plans Adjustment Attributable to Parent | Cumulative Effect, Period of Adoption, Adjusted Balance
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balances		(354,699)
Balances			(354,699)
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-Sale, Parent
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balances	15
OCI before reclassifications	7	5
Amounts reclassified from AOCI, net of tax	0	0
Other Comprehensive Income (Loss), Net of Tax, Total	7	5
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Noncontrolling Interest	0	0
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent, Total	7	5
Balances	22	15
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-Sale, Parent | Cumulative Effect, Period of Adoption, Adjusted Balance
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balances		10
Balances			10
Total
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balances	(539,694)	(567,636)	(560,139)
Other Comprehensive Income (Loss), Net of Tax, Total	730	27,942	(7,497)
Balances	$ (538,964)	$ (539,694)	$ (567,636)

Components of Accumulated Oth_4

Components of Accumulated Other Comprehensive Loss (Details 2) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Revenues	$ 2,342,645	$ 2,366,020	$ 2,133,981
Interest expense	(112,217)	(107,081)	(76,807)
Total costs and expenses	2,310,900	2,286,082	2,234,877
Income from continuing operations before income taxes	(101,670)	(52,670)	(167,897)
Income Tax Expense (Benefit)	17,066	30,866	4,856
Net income (loss)	$ 122,661	$ 88,098	$ 176,431
Discontinued Operation, Gain (Loss) on Disposal, Statement of Income or Comprehensive Income [Extensible Enumeration]	Other Operating Income (Expense), Net	Other Operating Income (Expense), Net
Reclassification out of Accumulated Other Comprehensive Income [Member] | Actuarial losses
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Pension and Other Postretirement Benefits Cost (Reversal of Cost)	$ 19,239	$ 18,917
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Defined Benefit Plans Adjustment Attributable to Parent
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Total costs and expenses	18,606	19,395
Income Tax Expense (Benefit)	(1,056)	(1,170)
Net income (loss)	17,550	18,225
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Defined Benefit Plans Adjustment, Net Prior Service Attributable to Parent
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Pension and Other Postretirement Benefits Cost (Reversal of Cost)	492	520
Reclassification out of Accumulated Other Comprehensive Income [Member] | Settlement/curtailment gain
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Pension and Other Postretirement Benefits Cost (Reversal of Cost)	(1,125)	(42)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Income Tax Expense (Benefit)	916	247
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Foreign Currency Adjustment Attributable to Parent
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax	(108)	(507)
Net income (loss)	(108)	(507)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Foreign currency exchange forward contracts | Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Revenues	(695)	1,638
Income from continuing operations before income taxes	(3,713)	(938)
Net income (loss)	(2,797)	(691)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Interest rate swaps | Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Interest expense	$ 3,018	$ 2,576

SCHEDULE II. VALUATION AND QU_2

SCHEDULE II. VALUATION AND QUALIFYING ACCOUNTS (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Increase (decrease) in valuation allowance	$ (5,400)
Allowance for Doubtful Accounts
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	15,522	$ 8,853	$ 12,235
Charged to Cost and Expenses	2,821	7,042	330
Due to Currency Translation Adjustments	(117)	(37)	(110)
Other	(3,112)	(336)	(3,602)
Balance at End of Period	15,114	15,522	8,853
Deferred Tax Assets - Valuation Allowance
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	177,888	132,954	130,902
Charged to Cost and Expenses	27,317	44,608	21,505
Due to Currency Translation Adjustments	(7,240)	3,721	(8,625)
Other	(5,220)	(3,395)	(10,828)
Balance at End of Period	192,745	177,888	132,954
Pension Adjustments
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Increase (decrease) in valuation allowance	$ (5,400)	(1,800)	(7,100)
Tax Rate Change
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Increase (decrease) in valuation allowance		$ 1,800	$ 4,300