Fair Value Measurements (Details) (USD $) In Millions	9 Months Ended
Sep. 30, 2011	Dec. 31, 2010
Other non-current assets
Available for sale investments	$ 29.0	$ 29.9
Other current assets:
Foreign exchange contracts	1.1	0.2
Commodity hedge contracts	0	0.8
Assets measured at fair value	30.1	30.9
Liabilities
Liabilities measured at fair value	(13.3)	(0.1)
Accrued Liabilities, Derivative [Member]
Liabilities
Commodity hedge contracts	(13.1)	(0.1)
Accrued Liabilities, Derivative [Member] \| Fair Value, Inputs, Level 1 [Member]
Liabilities
Commodity hedge contracts	0	0
Accrued Liabilities, Derivative [Member] \| Fair Value, Inputs, Level 2 [Member]
Liabilities
Commodity hedge contracts	(13.1)	(0.1)
Other Noncurrent Liabilities, Derivative [Member]
Liabilities
Commodity hedge contracts	(0.2)	0
Other Noncurrent Liabilities, Derivative [Member] \| Fair Value, Inputs, Level 1 [Member]
Liabilities
Commodity hedge contracts	0	0
Other Noncurrent Liabilities, Derivative [Member] \| Fair Value, Inputs, Level 2 [Member]
Liabilities
Commodity hedge contracts	(0.2)	0
Fair Value, Inputs, Level 1 [Member]
Other non-current assets
Available for sale investments	29.0	29.9
Other current assets:
Foreign exchange contracts	0	0
Commodity hedge contracts	0	0
Assets measured at fair value	29.0	29.9
Liabilities
Liabilities measured at fair value	0	0
Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Benchmark interest rates for contracts valued as liabilities	three and one-half percent or less
Benchmark interest rates for contracts valued as assets	less than one and one-half percent
Other non-current assets
Available for sale investments	0	0
Other current assets:
Foreign exchange contracts	1.1	0.2
Commodity hedge contracts	0	0.8
Assets measured at fair value	1.1	1.0
Liabilities
Liabilities measured at fair value	$ (13.3)	$ (0.1)

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 12

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Available-for-Sale Securities

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph e

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

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