Segment Reporting and Geographical Area Data - Segment Reporting (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Net sales	$ 883.4	$ 1,012.3	$ 960.9
Gross profit	332.3	346.0	302.0
Operating income	105.4	156.3	112.5
Adjustment to fair value of contingent consideration	9.4	40.7	1.9
Identifiable assets at year end	1,181.4	1,028.6	999.9
(Loss)/profit on disposal of subsidiary	(1.4)	1.6	0.0
Operating Segments [Member] \| Fuel Specialties [Member]
Segment Reporting Information [Line Items]
Net sales	509.6	532.8	566.8
Gross profit	186.4	176.0	170.8
Operating income	110.6	102.1	94.2
Identifiable assets at year end	397.2	408.9	408.2
Operating Segments [Member] \| Fuel Specialties [Member] \| Refinery and Performance [Member]
Segment Reporting Information [Line Items]
Net sales	388.9	408.0	440.2
Operating Segments [Member] \| Fuel Specialties [Member] \| Other [Member]
Segment Reporting Information [Line Items]
Net sales	120.7	124.8	126.6
Operating Segments [Member] \| Performance Chemicals [Member]
Segment Reporting Information [Line Items]
Net sales	138.7	155.0	177.6
Gross profit	43.4	42.4	43.7
Operating income	16.0	16.3	17.8
Identifiable assets at year end	340.0	120.2	156.6
Operating Segments [Member] \| Performance Chemicals [Member] \| Personal Care [Member]
Segment Reporting Information [Line Items]
Net sales	126.8	119.6	106.1
Operating Segments [Member] \| Performance Chemicals [Member] \| Fragrances [Member]
Segment Reporting Information [Line Items]
Net sales	0.1	23.0	56.2
Operating Segments [Member] \| Performance Chemicals [Member] \| Other [Member]
Segment Reporting Information [Line Items]
Net sales	11.8	12.4	15.3
Operating Segments [Member] \| Oilfield Services [Member]
Segment Reporting Information [Line Items]
Net sales	191.7	265.0	161.3
Gross profit	76.4	99.1	58.9
Operating income	(4.7)	9.0	18.0
Identifiable assets at year end	240.0	240.9	293.1
Operating Segments [Member] \| Octane Additives [Member]
Segment Reporting Information [Line Items]
Net sales	43.4	59.5	55.2
Gross profit	26.1	28.5	28.6
Operating income	22.7	24.7	22.6
Identifiable assets at year end	38.1	28.7	29.2
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Pension credit/(charge)	6.7	0.2	(3.3)
Corporate costs	(53.9)	(38.3)	(38.7)
Identifiable assets at year end	166.1	229.9	112.8
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
(Loss)/profit on disposal of subsidiary	$ (1.4)	$ 1.6	$ 0.0

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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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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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 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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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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