v2.4.0.6

Fair Value Measurements (Schedule Of Financial Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2011	Dec. 31, 2010
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Auction rate securities		$ 44.5
Supplemental executive retirement plan assets	26.5	23.0
Derivatives, net	13.2	16.4
Total financial assets	39.7	83.9
Quoted Prices In Active Markets For Identical Assets Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Supplemental executive retirement plan assets	26.5	23.0
Total financial assets	26.5	23.0
Significant Other Observable Inputs Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivatives, net	13.2	16.4
Total financial assets	13.2	16.4
Significant Unobservable Inputs Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Auction rate securities		44.5
Total financial assets		$ 44.5

X

- Definition

Fair Value Measured On Recurring Basis Supplemental Executive Retirement Plan Assets

+ References

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- Definition

Total Financial Assets

+ References

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X

- Definition

This element represents a certain statement of financial position asset caption which represents a class of assets, or which may include an individual asset, measured at fair value on a recurring basis.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph a

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X

- Definition

This element represents a certain statement of financial position asset caption which represents a class of assets, or which may include an individual asset, measured at fair value on a recurring basis.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph a

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