Schedule of Additions to Long-lived Assets and Depreciation and Amortization (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Segment Information [Line Items]
Additions to long-lived assets	$ 21,558	$ 18,923	$ 43,812	$ 42,206
Depreciation and amortization	28,492	29,323	57,270	55,130
Operating Segments [Member] \| Petroleum Additives [Member]
Segment Information [Line Items]
Additions to long-lived assets	16,449	17,644	36,723	38,948
Depreciation and amortization	18,700	19,019	37,679	38,093
Operating Segments [Member] \| All Other [Member]
Segment Information [Line Items]
Additions to long-lived assets	0	0	0	2
Depreciation and amortization	12	12	24	23
Operating Segments [Member] \| Specialty Materials [Member]
Segment Information [Line Items]
Additions to long-lived assets	4,139	981	5,027	2,418
Depreciation and amortization	8,864	9,381	17,722	15,020
Corporate, Non-Segment [Member]
Segment Information [Line Items]
Additions to long-lived assets	970	298	2,062	838
Depreciation and amortization	$ 916	$ 911	$ 1,845	$ 1,994

- Definition

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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