Fair Value Measurements (Details) (Recurring [Member], USD $) In Millions, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Carrying Amount [Member]
Non-derivatives:
Cash and cash equivalents, Assets	$ 43.2	$ 22.4
Short-term investments, Assets	5.0	5.1
Non-derivatives:
Long-term debt (including current portion), Liabilities	37.0	30.0
Fair value [Member]
Non-derivatives:
Cash and cash equivalents, Assets	43.2	22.4
Short-term investments, Assets	5.0	5.1
Non-derivatives:
Long-term debt (including current portion), Liabilities	37.0	30.0
Non-financial assets and liabilities (Level 3 measurement) [Member] \| Carrying Amount [Member]
Non-financial liabilities (Level 3 measurement):
Acquisition-related contingent consideration	4.4	4.3
Non-financial assets and liabilities (Level 3 measurement) [Member] \| Carrying Amount [Member] \| Octane Additives [Member]
Non-financial assets (Level 3 measurement):
Goodwill-Octane Additives	0.9	1.3
Non-financial assets and liabilities (Level 3 measurement) [Member] \| Carrying Amount [Member] \| Phantom Share Units PSUs [Member]
Non-financial liabilities (Level 3 measurement):
Stock equivalent units	12.0	12.6
Non-financial assets and liabilities (Level 3 measurement) [Member] \| Fair value [Member]
Non-financial liabilities (Level 3 measurement):
Acquisition-related contingent consideration	4.4	4.3
Non-financial assets and liabilities (Level 3 measurement) [Member] \| Fair value [Member] \| Octane Additives [Member]
Non-financial assets (Level 3 measurement):
Goodwill-Octane Additives	0.9	1.3
Non-financial assets and liabilities (Level 3 measurement) [Member] \| Fair value [Member] \| Phantom Share Units PSUs [Member]
Non-financial liabilities (Level 3 measurement):
Stock equivalent units	12.0	12.6
Derivatives (Level 1 measurement) [Member] \| Carrying Amount [Member]
Derivatives (Level 1 measurement):
Other non-current assets - commodity swaps, Assets	0	0.1
Foreign currency forward exchange contracts, Assets	0	0.8
Derivatives (Level 1 measurement):
Foreign currency forward exchange contracts, Liabilities	1.2	0
Derivatives (Level 1 measurement) [Member] \| Fair value [Member]
Derivatives (Level 1 measurement):
Other non-current assets - commodity swaps, Assets	0	0.1
Foreign currency forward exchange contracts, Assets	0	0.8
Derivatives (Level 1 measurement):
Foreign currency forward exchange contracts, Liabilities	$ 1.2	$ 0

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