Segment Reporting - Segment Reporting (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Segment Reporting Information [Line Items]
Net sales	$ 228.0	$ 242.9	$ 440.1	$ 512.1
Gross profit	85.5	87.5	161.7	169.3
Adjustment to fair value of contingent consideration	2.4	26.6	4.0	23.1
Loss on disposal of subsidiary	0.0	0.0	(1.4)	0.0
Operating income	28.6	57.4	54.2	80.8
Operating Segments [Member] \| Fuel Specialties [Member]
Segment Reporting Information [Line Items]
Net sales	129.3	121.8	252.7	265.3
Gross profit	43.7	44.0	85.7	85.9
Operating income	24.2	25.6	48.1	49.1
Operating Segments [Member] \| Performance Chemicals [Member]
Segment Reporting Information [Line Items]
Net sales	35.3	43.9	70.0	90.7
Gross profit	11.3	11.3	22.1	23.4
Operating income	4.7	4.7	9.1	9.5
Operating Segments [Member] \| Oilfield Services [Member]
Segment Reporting Information [Line Items]
Net sales	46.5	70.7	82.7	137.4
Gross profit	19.9	28.4	31.5	50.4
Operating income	(1.6)	5.0	(7.1)	6.6
Operating Segments [Member] \| Octane Additives [Member]
Segment Reporting Information [Line Items]
Net sales	16.9	6.5	34.7	18.7
Gross profit	10.6	3.8	22.4	9.6
Operating income	9.6	2.8	20.6	7.9
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Pension credit	1.7	0.1	3.5	0.1
Corporate costs	$ (12.4)	$ (7.4)	$ (22.6)	$ (15.5)

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
-Topic 805
-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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-SubTopic 20
-Section 50
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-Subparagraph (h)
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- Definition

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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-Publisher FASB
-Name Accounting Standards Codification
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The net result for the period of deducting operating expenses from operating revenues.

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- Definition

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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- Definition

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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