Commitments and Contingencies (Personal Injury Liability Activity) (Details) (Personal Injury [Member], USD $) In Millions	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010
Personal Injury [Member]
Personal Injury Liability Activity [Roll Forward]
Balance at beginning of year	$ 62.2	$ 86.9
Accruals	8.1	10.9
Change in estimate	(12.2)	(12.5)
Payments	(12.1)	(13.1)
Balance at end of period	$ 46.0	$ 72.2

The charge against earnings in the period to change the loss contingency reserves for change in estimates.

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- Definition

The carrying amount as of the balance sheet date of the combined total of loss contingency liabilities.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 5

-Paragraph 9, 10, 11, 12

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6952336&loc=d3e14326-108349

+ Details

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- Definition

The payments made in the period which reduced loss contingency liabilities.

+ References

+ Details

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- Definition

The charge against earnings in the period to increase loss contingency liabilities, net of any adjustments to reduce previously estimated charges.

+ References

+ Details

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ Details

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