Segment Reporting and Geographical Area Data - Segment Reporting (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Net sales	$ 1,476.9	$ 1,306.8	$ 883.4
Gross profit	435.0	403.3	332.3
Restructuring charge	7.1	0.0	0.0
Adjustment to fair value of contingent consideration	0.0	0.0	9.4
Loss on disposal of subsidiary	0.0	(0.9)	(1.4)
Foreign exchange loss on liquidation of subsidiary	0.0	(1.8)	0.0
Operating income	133.5	125.0	98.2
Identifiable assets at year end	1,473.4	1,410.2	1,181.4
Operating Segments [Member] \| Fuel Specialties [Member]
Segment Reporting Information [Line Items]
Net sales	574.5	523.8	509.6
Gross profit	195.0	188.2	186.4
Operating income	116.3	107.7	111.1
Identifiable assets at year end	470.5	437.0	397.2
Operating Segments [Member] \| Fuel Specialties [Member] \| Refinery and Performance [Member]
Segment Reporting Information [Line Items]
Net sales	432.1	397.0	388.9
Operating Segments [Member] \| Fuel Specialties [Member] \| Other [Member]
Segment Reporting Information [Line Items]
Net sales	142.4	126.8	120.7
Operating Segments [Member] \| Performance Chemicals [Member]
Segment Reporting Information [Line Items]
Net sales	468.1	419.5	138.7
Gross profit	97.5	75.8	43.4
Operating income	44.7	32.6	16.0
Identifiable assets at year end	463.9	480.8	340.0
Operating Segments [Member] \| Performance Chemicals [Member] \| Personal Care [Member]
Segment Reporting Information [Line Items]
Net sales	241.4	206.5	126.8
Operating Segments [Member] \| Performance Chemicals [Member] \| Home Care [Member]
Segment Reporting Information [Line Items]
Net sales	109.1	103.4	2.0
Operating Segments [Member] \| Performance Chemicals [Member] \| Other [Member]
Segment Reporting Information [Line Items]
Net sales	117.6	109.6	9.9
Operating Segments [Member] \| Oilfield Services [Member]
Segment Reporting Information [Line Items]
Net sales	400.6	304.4	191.7
Gross profit	130.4	109.3	76.4
Operating income	22.1	9.5	(4.7)
Identifiable assets at year end	296.1	256.6	240.0
Operating Segments [Member] \| Octane Additives [Member]
Segment Reporting Information [Line Items]
Net sales	33.7	59.1	43.4
Gross profit	12.1	30.0	26.1
Operating income	9.9	26.7	22.7
Identifiable assets at year end	39.6	41.7	38.1
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Corporate costs	(52.4)	(48.8)	(54.9)
Restructuring charge	(7.1)	0.0	0.0
Identifiable assets at year end	203.3	194.1	166.1
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Loss on disposal of subsidiary	$ 0.0	$ (0.9)	$ (1.4)

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