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v3.25.3

Segment Reporting - Segment Reporting (Detail) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Segment Reporting Information [Line Items] |  |  |  |
Net sales | $ 441.9 | $ 443.4 | $ 1,322.4 | $ 1,378.6
Gross profit | 116.7 | 124.1 | 365.0 | 406.7
Adjustment to fair value of contingent consideration | 17.7 | (0.7) | 16.2 | (2.1)
Restructuring charge | 0.9 | 0.0 | 0.9 | 0.0
Impairment of property, plant and equipment | 22.9 | 0.0 | 22.9 | 0.0
Impairment of intangible assets | 19.1 | 0.0 | 19.1 | 0.0
Profit on disposal of property, plant and equipment | 0.0 | 0.1 | 0.2 | 0.2
Operating income/(loss) | 5.9 | 45.6 | 82.7 | 136.8
Operating Segments [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Adjustment to fair value of contingent consideration | 17.7 | (0.7) | 16.2 | (2.1)
Restructuring charge | (0.9) | 0.0 | (0.9) | 0.0
Impairment of property, plant and equipment | (22.9) | 0.0 | (22.9) | 0.0
Impairment of intangible assets | (19.1) | 0.0 | (19.1) | 0.0
Profit on disposal of property, plant and equipment | 0.0 | 0.1 | 0.2 | 0.2
Operating Segments [Member] | Performance Chemicals [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net sales | 170.8 | 163.6 | 513.0 | 484.5
Gross profit | 25.8 | 36.1 | 91.6 | 110.0
Operating income/(loss) | 9.2 | 20.0 | 43.3 | 62.3
Operating Segments [Member] | Fuel Specialties [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net sales | 172.0 | 165.8 | 507.4 | 509.3
Gross profit | 61.2 | 55.7 | 184.9 | 173.9
Operating income/(loss) | 35.3 | 30.9 | 107.6 | 94.7
Operating Segments [Member] | Oilfield Services [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net sales | 99.1 | 114.0 | 302.0 | 384.8
Gross profit | 29.7 | 32.3 | 88.5 | 122.8
Operating income/(loss) | 4.8 | 7.1 | 15.1 | 31.3
Operating Segments [Member] | Personal Care [Member] | Performance Chemicals [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net sales | 103.9 | 98.6 | 309.4 | 291.1
Operating Segments [Member] | Home Care [Member] | Performance Chemicals [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net sales | 27.9 | 26.5 | 80.2 | 77.2
Operating Segments [Member] | Other [Member] | Performance Chemicals [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net sales | 39.0 | 38.5 | 123.4 | 116.2
Operating Segments [Member] | Refinery and Performance [Member] | Fuel Specialties [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net sales | 120.2 | 120.9 | 362.4 | 375.1
Operating Segments [Member] | Other [Member] | Fuel Specialties [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net sales | 51.8 | 44.9 | 145.0 | 134.2
Corporate, Non-Segment [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Corporate costs | $ (18.2) | $ (11.8) | $ (56.8) | $ (49.6)

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