Commitments and Contingencies Personal Injury Liability Activity (Details) (Personal Injury [Member], USD $) In Millions, unless otherwise specified	6 Months Ended
Jun. 30, 2014	Jun. 30, 2013
Personal Injury [Member]
Personal Injury Liability Activity [Roll Forward]
Balance at beginning of year	$ 31.2	$ 34.4
Accruals	4.4	4.4
Change in estimate	(0.7)	4.1
Payments	(3.8)	(5.6)
Balance at end of period	$ 31.1	$ 37.3

Amount charged against operating income increasing (decreasing) the loss contingency liability for a change in estimate.

No definition available.

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- Definition

Amount of loss contingency liability.

+ References

Reference 1: 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=25496072&loc=d3e14326-108349

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- Definition

Amount of payments made reducing loss contingency liability.

+ References

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- Definition

Amount charged against operating income increasing loss contingency liability, after adjustments to reduce previously estimated charges.

+ References

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