The following table summarizes the changes in goodwill by reportable segment for the years ended December 31, 2025 and 2024 (in thousands):


	Energy Storage		Specialties		Ketjen		Total
Balance at December 31, 2023(a)	$	1,424,484	$	32,639	$	172,606	$	1,629,729





Foreign currency translation adjustments	(36,893)		(62)		(10,060)		(47,015)
Balance at December 31, 2024(a)	1,387,591		32,577		162,546		1,582,714



Impairment loss(b)	—		—		(181,070)		(181,070)
Foreign currency translation adjustments	79,368		121		18,524		98,013
Balance at December 31, 2025(c)	$	1,466,959	$	32,698	$	—	$	1,499,657

(a) Balance as of December 31, 2024 and 2023 included an accumulated impairment loss of $6.8 million from the PCS reporting unit within the Ketjen segment. As a result, the balance of Ketjen goodwill as of December 31, 2024 and 2023 fully consisted of goodwill related to the Refining Solutions reporting unit. The balances of Energy Storage and Specialties goodwill as of December 31, 2024 and 2023 fully consisted of goodwill related to the Energy Storage and Specialties reporting units, respectively.

(c) Balance as of December 31, 2025 included an accumulated impairment loss of $187.8 million from the Refining Solutions and PCS reporting units within the Ketjen segment. The balances of Energy Storage and Specialties goodwill as of December 31, 2025 fully consisted of goodwill related to the Energy Storage and Specialties reporting units, respectively.


	Customer Lists and Relationships		Trade Names and Trademarks(a)		Patents and Technology		Other		Total
Gross Asset Value
Balance at December 31, 2023	$	417,803	$	13,405	$	46,287	$	34,649	$	512,144

Retirements	—		(2,309)		(14,506)		(4,449)		(21,264)
Foreign currency translation adjustments and other	(15,791)		(426)		484		(1,190)		(16,923)
Balance at December 31, 2024	402,012		10,670		32,265		29,010		473,957


Reclass to assets held for sale(b)	(45,289)		(10,357)		(2,900)		(111)		(58,657)
Foreign currency translation adjustments and other	27,608		705		3,115		1,534		32,962
Balance at December 31, 2025	$	384,331	$	1,018	$	32,480	$	30,433	$	448,262
Accumulated Amortization
Balance at December 31, 2023	$	(204,481)	$	(3,673)	$	(26,758)	$	(15,374)	$	(250,286)
Amortization	(19,570)		—		(2,549)		(917)		(23,036)
Retirements	—		2,309		14,506		4,449		21,264
Foreign currency translation adjustments and other	7,820		40		548		446		8,854
Balance at December 31, 2024	(216,231)		(1,324)		(14,253)		(11,396)		(243,204)
Amortization	(18,896)		—		(2,576)		(958)		(22,430)

Reclass to assets held for sale(b)	43,914		1,324		2,268		111		47,617
Foreign currency translation adjustments and other	(14,858)		—		(701)		(453)		(16,012)
Balance at December 31, 2025	$	(206,071)	$	—	$	(15,262)	$	(12,696)	$	(234,029)
Net Book Value at December 31, 2024	$	185,781	$	9,346	$	18,012	$	17,614	$	230,753
Net Book Value at December 31, 2025	$	178,260	$	1,018	$	17,218	$	17,737	$	214,233

Amortization of other intangibles amounted to $22.4 million, $23.0 million and $28.0 million for the years ended December 31, 2025, 2024 and 2023, respectively. Included in amortization for the years ended December 31, 2025, 2024 and 2023 is $16.0 million, $16.1 million and $16.7 million, respectively, of amortization using the pattern of economic benefit method.