v2.4.0.6

Fair Value Measurements (Summary Of Fair Value Measurements Of Auction Rate Securities Using Significant Level 3 Inputs) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2011		Mar. 31, 2010
Fair Value Measurements [Abstract]
Beginning Balance	$ 44.5		$ 60.5
Sales	(49.3)		(5.4)
Realized losses	(0.1)	[1]		[1]
Unrealized gains	4.9	[1]	0.3	[1]
Transfers in and/or out of Level 3
Ending balance			$ 55.4
[1] Realized losses and unrealized gains are included in other income, net, in our condensed consolidated statements of income.

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- Definition

Transfers In And Or Out Of Level Three

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No definition available.

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- Definition

This element represents total gains or losses for the period (realized and unrealized), arising from assets measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in earnings or resulted in a change in net asset value.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph c(1)

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- Definition

This element represents total gains or losses for the period (realized and unrealized), arising from assets measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in other comprehensive income (a separate component of shareholders' equity.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

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- Definition

This element represents purchases, sales, issuances, and settlements (net) which have taken place during the period in relation to assets measured at fair value on a recurring basis using unobservable inputs (Level 3).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph c(2)

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- Definition

This element represents an asset measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph c

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