Segment Reporting - Segment Reporting (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Segment Reporting Information [Line Items]
Net sales	$ 294.3	$ 212.1
Gross profit	90.9	76.2
Adjustment to fair value of contingent consideration	0.0	1.6
Loss on disposal of subsidiary	0.0	(1.4)
Foreign exchange loss on liquidation of subsidiary	(1.8)	0.0
Operating income	26.4	25.6
Operating Segments [Member] \| Fuel Specialties [Member]
Segment Reporting Information [Line Items]
Net sales	126.4	123.4
Gross profit	46.1	42.0
Operating income	26.8	23.9
Operating Segments [Member] \| Fuel Specialties [Member] \| Refinery and Performance [Member]
Segment Reporting Information [Line Items]
Net sales	100.4	98.2
Operating Segments [Member] \| Fuel Specialties [Member] \| Other [Member]
Segment Reporting Information [Line Items]
Net sales	26.0	25.2
Operating Segments [Member] \| Performance Chemicals [Member]
Segment Reporting Information [Line Items]
Net sales	94.5	34.7
Gross profit	16.7	10.8
Operating income	6.0	4.4
Operating Segments [Member] \| Performance Chemicals [Member] \| Personal Care [Member]
Segment Reporting Information [Line Items]
Net sales	47.5	32.3
Operating Segments [Member] \| Performance Chemicals [Member] \| Home Care [Member]
Segment Reporting Information [Line Items]
Net sales	26.9	0.3
Operating Segments [Member] \| Performance Chemicals [Member] \| Other [Member]
Segment Reporting Information [Line Items]
Net sales	20.1	2.1
Operating Segments [Member] \| Oilfield Services [Member]
Segment Reporting Information [Line Items]
Net sales	66.5	36.2
Gross profit	25.4	11.6
Operating income	3.0	(5.5)
Operating Segments [Member] \| Octane Additives [Member]
Segment Reporting Information [Line Items]
Net sales	6.9	17.8
Gross profit	2.7	11.8
Operating income	2.0	11.0
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Pension credit	1.1	1.8
Corporate costs	(10.7)	(10.2)
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Loss on disposal of subsidiary	$ 0.0	$ (1.4)

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- Definition

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

+ References

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The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

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Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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Amount of gain (loss) on sale or disposal of equity in securities of subsidiaries.

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Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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