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Intangibles (Net of Amortization) and Goodwill (Narrative) (Details) - USD ($)	Jun. 30, 2026	Dec. 31, 2025
Intangible Asset, Finite-Lived [Line Items]
Net carrying amount of intangibles and goodwill	$ 923,182,000	$ 941,156,000
Accumulated goodwill impairment	0	$ 0
Petroleum Additives [Member]
Intangible Asset, Finite-Lived [Line Items]
Net carrying amount of intangibles and goodwill	124,000,000
Specialty Materials [Member]
Intangible Asset, Finite-Lived [Line Items]
Net carrying amount of intangibles and goodwill	$ 799,000,000
Formulas And Technology [Member] \| Minimum [Member]
Intangible Asset, Finite-Lived [Line Items]
Estimated economic life, in years	8 years
Formulas And Technology [Member] \| Maximum [Member]
Intangible Asset, Finite-Lived [Line Items]
Estimated economic life, in years	20 years
Customer Bases [Member] \| Minimum [Member]
Intangible Asset, Finite-Lived [Line Items]
Estimated economic life, in years	9 years
Customer Bases [Member] \| Maximum [Member]
Intangible Asset, Finite-Lived [Line Items]
Estimated economic life, in years	20 years
Trademarks and Trade Names \| Minimum [Member]
Intangible Asset, Finite-Lived [Line Items]
Estimated economic life, in years	5 years
Trademarks and Trade Names \| Maximum [Member]
Intangible Asset, Finite-Lived [Line Items]
Estimated economic life, in years	15 years
Order or Production Backlog
Intangible Asset, Finite-Lived [Line Items]
Estimated economic life, in years	5 years