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 Amount		Accumulated Amortization		Gross Carrying Amount		Accumulated Amortization
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.