Segment Reporting - Segment Reporting (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Segment Reporting Information [Line Items]
Net sales	$ 205.5	$ 254.2	$ 645.6	$ 766.3
Gross profit	79.2	90.4	240.9	259.7
Adjustment to fair value of contingent consideration	2.3	8.5	6.3	31.6
Profit/(loss) on disposal of subsidiary	0.0	1.6	(1.4)	1.6
Operating income	18.9	41.2	73.1	122.0
Operating Segments [Member] \| Fuel Specialties [Member]
Segment Reporting Information [Line Items]
Net sales	114.4	121.3	367.1	386.6
Gross profit	43.8	39.5	129.5	125.4
Operating income	24.1	21.6	72.2	70.7
Operating Segments [Member] \| Performance Chemicals [Member]
Segment Reporting Information [Line Items]
Net sales	36.8	33.7	106.8	124.4
Gross profit	12.3	9.9	34.4	33.3
Operating income	4.2	3.6	13.3	13.1
Operating Segments [Member] \| Oilfield Services [Member]
Segment Reporting Information [Line Items]
Net sales	49.7	78.9	132.4	216.3
Gross profit	20.6	32.0	52.1	82.4
Operating income	0.0	7.2	(7.1)	13.8
Operating Segments [Member] \| Octane Additives [Member]
Segment Reporting Information [Line Items]
Net sales	4.6	20.3	39.3	39.0
Gross profit	2.5	9.0	24.9	18.6
Operating income	1.9	8.0	22.5	15.9
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Pension credit	1.6	0.0	5.1	0.1
Corporate costs	$ (15.2)	$ (9.3)	$ (37.8)	$ (24.8)

Corporate costs.

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
-Section 50
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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of gain (loss) on sale or disposal of equity in securities of subsidiaries.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (13)(g)
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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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The net result for the period of deducting operating expenses from operating revenues.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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