Segment Reporting - Segment Reporting (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Segment Reporting Information [Line Items]
Net sales	$ 443.4	$ 464.1	$ 1,378.6	$ 1,454.1
Adjustment to fair value of contingent consideration	(0.7)	0.0	(2.1)	0.0
Profit on disposal of property, plant and equipment	0.1	0.0	0.2	0.0
Operating income/(loss)	45.6	41.9	136.8	117.1
Operating Segments [Member]
Segment Reporting Information [Line Items]
Adjustment to fair value of contingent consideration	(0.7)	0.0	(2.1)	0.0
Profit on disposal of property, plant and equipment	0.1	0.0	0.2	0.0
Operating Segments [Member] \| Performance Chemicals [Member]
Segment Reporting Information [Line Items]
Net sales	163.6	145.2	484.5	424.4
Operating income/(loss)	20.0	16.9	62.3	36.5
Operating Segments [Member] \| Fuel Specialties [Member]
Segment Reporting Information [Line Items]
Net sales	165.8	169.3	509.3	513.8
Operating income/(loss)	30.9	27.6	94.7	77.1
Operating Segments [Member] \| Oilfield Services [Member]
Segment Reporting Information [Line Items]
Net sales	114.0	149.6	384.8	515.9
Operating income/(loss)	7.1	16.4	31.3	60.3
Operating Segments [Member] \| Personal Care [Member] \| Performance Chemicals [Member]
Segment Reporting Information [Line Items]
Net sales	98.6	97.0	291.1	263.8
Operating Segments [Member] \| Home Care [Member] \| Performance Chemicals [Member]
Segment Reporting Information [Line Items]
Net sales	26.5	22.3	77.2	65.7
Operating Segments [Member] \| Other [Member] \| Performance Chemicals [Member]
Segment Reporting Information [Line Items]
Net sales	38.5	25.9	116.2	94.9
Operating Segments [Member] \| Refinery and Performance [Member] \| Fuel Specialties [Member]
Segment Reporting Information [Line Items]
Net sales	120.9	126.0	375.1	394.6
Operating Segments [Member] \| Other [Member] \| Fuel Specialties [Member]
Segment Reporting Information [Line Items]
Net sales	44.9	43.3	134.2	119.2
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Corporate costs	$ (11.8)	$ (19.0)	$ (49.6)	$ (56.8)

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