Segment Reporting - Segment Reporting (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Segment Reporting Information [Line Items]
Net sales	$ 332.4	$ 205.5	$ 953.0	$ 645.6
Gross profit	98.8	79.2	294.8	240.9
Adjustment to fair value of contingent consideration	0.0	2.3	0.0	6.3
Loss on disposal of subsidiary	0.0	0.0	(1.0)	(1.4)
Foreign exchange loss on liquidation of subsidiary	0.0	0.0	(1.8)	0.0
Operating income	30.2	18.9	91.3	73.1
Operating Segments [Member] \| Fuel Specialties [Member]
Segment Reporting Information [Line Items]
Net sales	130.1	114.4	377.8	367.1
Gross profit	44.6	43.8	135.9	129.5
Operating income	24.9	24.1	75.5	72.2
Operating Segments [Member] \| Fuel Specialties [Member] \| Refinery and Performance [Member]
Segment Reporting Information [Line Items]
Net sales	97.4	89.8	286.5	281.7
Operating Segments [Member] \| Fuel Specialties [Member] \| Other [Member]
Segment Reporting Information [Line Items]
Net sales	32.7	24.6	91.3	85.4
Operating Segments [Member] \| Performance Chemicals [Member]
Segment Reporting Information [Line Items]
Net sales	110.3	36.8	309.7	106.8
Gross profit	20.7	12.3	54.8	34.4
Operating income	9.7	4.2	22.2	13.3
Operating Segments [Member] \| Performance Chemicals [Member] \| Personal Care [Member]
Segment Reporting Information [Line Items]
Net sales	52.2	33.7	148.4	97.7
Operating Segments [Member] \| Performance Chemicals [Member] \| Home Care [Member]
Segment Reporting Information [Line Items]
Net sales	32.7	0.5	89.0	1.4
Operating Segments [Member] \| Performance Chemicals [Member] \| Other [Member]
Segment Reporting Information [Line Items]
Net sales	25.4	2.6	72.3	7.7
Operating Segments [Member] \| Oilfield Services [Member]
Segment Reporting Information [Line Items]
Net sales	81.9	49.7	224.5	132.4
Gross profit	28.5	20.6	82.9	52.1
Operating income	1.8	0.0	8.5	(7.1)
Operating Segments [Member] \| Octane Additives [Member]
Segment Reporting Information [Line Items]
Net sales	10.1	4.6	41.0	39.3
Gross profit	5.0	2.5	21.2	24.9
Operating income	4.4	1.9	19.2	22.5
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Pension credit	1.1	1.6	3.2	5.1
Corporate costs	(11.7)	(15.2)	(34.5)	(37.8)
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Loss on disposal of subsidiary	$ 0.0	$ 0.0	$ (1.0)	$ (1.4)

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Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

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