Employee Benefit Plans (Schedule of Effect of One-Percentage Point Change in Assumed Health Care Cost Trend Rates) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014
General Discussion of Pension and Other Postretirement Benefits [Abstract]
1-Percent Point Increase, Effect on total of service and interest cost	$ 0.2
1-Percent Point Decrease, Effect on total of service and interest cost	(0.2)
1-Percent Point Increase, Effect on postretirement benefit obligation	4.7
1-Percent Point Decrease, Effect on postretirement benefit obligation	$ (3.8)

Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (m)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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- Definition

Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

+ References

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- Definition

The effect of a one-percentage-point increase in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

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The effect of a one-percentage-point increase in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

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