Postretirement Health Care and Life Insurance Benefits (Details 4) (Postretirement Health Care and Life Insurance Benefits [Member], USD $) In Millions, unless otherwise specified	Dec. 31, 2014
Postretirement Health Care and Life Insurance Benefits [Member]
Estimated Future Benefit Payments
Postretirement Benefits, 2015	$ 57.2
Postretirement Benefits, 2016	59.0
Postretirement Benefits, 2017	59.9
Postretirement Benefits, 2018	60.4
Postretirement Benefits, 2019	60.7
Postretirement Benefits, Years 2020-2024	$ 297.6

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Amount of benefits expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (f)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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Amount of benefits expected to be paid in the next fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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Amount of benefits expected to be paid in the fifth fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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Amount of benefits expected to be paid in the fourth fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the third fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the second fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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