Segment Reporting - Segment Reporting (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Segment Reporting Information [Line Items]
Net sales	$ 440.8	$ 500.2
Gross profit	125.1	155.7
Adjustment to fair value of contingent consideration	(0.7)	(0.8)
Profit on disposal of property, plant and equipment	0.1	0.1
Operating income/(loss)	42.5	50.5
Operating Segments [Member]
Segment Reporting Information [Line Items]
Adjustment to fair value of contingent consideration	(0.7)	(0.8)
Profit on disposal of property, plant and equipment	0.1	0.1
Operating Segments [Member] \| Performance Chemicals [Member]
Segment Reporting Information [Line Items]
Net sales	168.4	160.8
Gross profit	35.3	37.7
Operating income/(loss)	19.8	21.1
Operating Segments [Member] \| Fuel Specialties [Member]
Segment Reporting Information [Line Items]
Net sales	170.3	176.9
Gross profit	60.8	60.6
Operating income/(loss)	36.9	33.4
Operating Segments [Member] \| Oilfield Services [Member]
Segment Reporting Information [Line Items]
Net sales	102.1	162.5
Gross profit	29.0	57.4
Operating income/(loss)	4.1	16.9
Operating Segments [Member] \| Personal Care [Member] \| Performance Chemicals [Member]
Segment Reporting Information [Line Items]
Net sales	100.6	94.8
Operating Segments [Member] \| Home Care [Member] \| Performance Chemicals [Member]
Segment Reporting Information [Line Items]
Net sales	26.3	26.4
Operating Segments [Member] \| Other [Member] \| Performance Chemicals [Member]
Segment Reporting Information [Line Items]
Net sales	41.5	39.6
Operating Segments [Member] \| Refinery and Performance [Member] \| Fuel Specialties [Member]
Segment Reporting Information [Line Items]
Net sales	129.4	145.1
Operating Segments [Member] \| Other [Member] \| Fuel Specialties [Member]
Segment Reporting Information [Line Items]
Net sales	40.9	31.8
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Corporate costs	$ (17.7)	$ (20.2)

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