Goodwill - Summary of Goodwill (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Goodwill [Line Items]
At January 1, Gross cost	$ 424.4us-gaap_GoodwillGross	$ 384.2us-gaap_GoodwillGross
At January 1, Accumulated impairment losses	(236.5)	(235.2)
At January 1, Net book amount	187.9us-gaap_Goodwill	149.0us-gaap_Goodwill
Exchange effect	(0.4)us-gaap_GoodwillTranslationAdjustments	0us-gaap_GoodwillTranslationAdjustments
Acquisitions	88.1us-gaap_GoodwillAcquiredDuringPeriod	39.6us-gaap_GoodwillAcquiredDuringPeriod
Adjustments to purchase price allocation	0.5	0.6
Impairment losses	0us-gaap_GoodwillImpairmentLoss	(1.3)us-gaap_GoodwillImpairmentLoss	(1.2)us-gaap_GoodwillImpairmentLoss
At December 31, Gross cost	512.6us-gaap_GoodwillGross	424.4us-gaap_GoodwillGross	384.2us-gaap_GoodwillGross
At December 31, Accumulated impairment losses	(236.5)	(236.5)	(235.2)
At December 31, Net book amount	276.1us-gaap_Goodwill	187.9us-gaap_Goodwill	149.0us-gaap_Goodwill
Fuel Specialties [Member]
Goodwill [Line Items]
At January 1, Gross cost	141.1	117.6
At January 1, Accumulated impairment losses	0	0
At January 1, Net book amount	141.1	117.6
Exchange effect	(0.3)	0
Acquisitions	88.1	22.9
Adjustments to purchase price allocation	0.5	0.6
Impairment losses	0	0
At December 31, Gross cost	229.4	141.1
At December 31, Accumulated impairment losses	0	0
At December 31, Net book amount	229.4	141.1
Performance Chemicals [Member]
Goodwill [Line Items]
At January 1, Gross cost	46.8	30.1
At January 1, Accumulated impairment losses	0	0
At January 1, Net book amount	46.8	30.1
Exchange effect	(0.1)	0
Acquisitions	0	16.7
Adjustments to purchase price allocation	0	0
Impairment losses	0	0
At December 31, Gross cost	46.7	46.8
At December 31, Accumulated impairment losses	0	0
At December 31, Net book amount	46.7	46.8
Octane Additives [Member]
Goodwill [Line Items]
At January 1, Gross cost	236.5	236.5
At January 1, Accumulated impairment losses	(236.5)	(235.2)
At January 1, Net book amount	0	1.3
Exchange effect	0	0
Acquisitions	0	0
Adjustments to purchase price allocation	0	0
Impairment losses	0	(1.3)
At December 31, Gross cost	236.5	236.5
At December 31, Accumulated impairment losses	(236.5)	(236.5)
At December 31, Net book amount	$ 0	$ 0

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase (decrease) from foreign currency translation adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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