Segmental Reporting and Geographical Area Data (Details 1) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Segment reporting on the basis of geographical location
Net sales	$ 776.4	$ 774.4	$ 683.2
Income before income taxes	95.2	52.6	70.7
Long-lived assets at year end	71.7	65.3	68.4
Identifiable assets at year end	579.4	568.8	549.4
Goodwill [Member]
Segment reporting on the basis of geographical location
Identifiable assets at year end	149.0	141.5	143.6
Impairment of Octane Additives segment goodwill [Member]
Segment reporting on the basis of geographical location
Net sales	69.6	76.2	72.4
Income before income taxes	(1.2)	(2.0)	(2.2)
Identifiable assets at year end	48.9	51.5	65.9
United States [Member]
Segment reporting on the basis of geographical location
Income before income taxes	5.6	(42.6)	11.1
Long-lived assets at year end	31.5	22.0	16.7
Identifiable assets at year end	174.1	123.2	97.4
United Kingdom [Member]
Segment reporting on the basis of geographical location
Income before income taxes	38.2	39.0	25.5
Long-lived assets at year end	28.7	32.4	40.1
Identifiable assets at year end	192.1	253.8	255.5
Rest of Europe [Member]
Segment reporting on the basis of geographical location
Income before income taxes	52.6	58.2	36.6
Long-lived assets at year end	11.5	10.9	11.6
Identifiable assets at year end	63.8	49.8	52.4
Other [Member]
Segment reporting on the basis of geographical location
Income before income taxes	0	0	(0.3)
Identifiable assets at year end	0.4	0.5	0.5
Sales by source [Member]
Segment reporting on the basis of geographical location
Net sales	776.4	774.4	683.2
Sales by source [Member] \| United States [Member]
Segment reporting on the basis of geographical location
Net sales	274.1	265.6	238.4
Sales by source [Member] \| United Kingdom [Member]
Segment reporting on the basis of geographical location
Net sales	475.1	482.8	431.8
Sales by source [Member] \| Rest of Europe [Member]
Segment reporting on the basis of geographical location
Net sales	142.8	151.7	106.8
Sales by source [Member] \| Other [Member]
Segment reporting on the basis of geographical location
Net sales	0.5	0.9	0.7
Sales by source [Member] \| Sales between areas [Member]
Segment reporting on the basis of geographical location
Net sales	(116.1)	(126.6)	(94.5)
Sales by destination [Member]
Segment reporting on the basis of geographical location
Net sales	776.4	774.4	683.2
Sales by destination [Member] \| United States [Member]
Segment reporting on the basis of geographical location
Net sales	272.4	248.2	231.4
Sales by destination [Member] \| United Kingdom [Member]
Segment reporting on the basis of geographical location
Net sales	38.8	48.5	26.8
Sales by destination [Member] \| Rest of Europe [Member]
Segment reporting on the basis of geographical location
Net sales	331.0	304.2	235.1
Sales by destination [Member] \| Other [Member]
Segment reporting on the basis of geographical location
Net sales	$ 134.2	$ 173.5	$ 189.9

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

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This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

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

-Publisher SEC

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Long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets.

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

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

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