Pension and Other Post-Retirement Benefits (Details 6) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	457.0
Common Stock [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets
Domestic defined benefit pension plans [Member]
Weighted-average asset allocations of domestic funded pension plans
Target asset allocation percentage	100.00%
Actual plan asset allocations	100.00%	100.00%
Domestic defined benefit pension plans [Member] \| Equity Securities [Member]
Weighted-average asset allocations of domestic funded pension plans
Target asset allocation percentage	52.00%
Actual plan asset allocations	51.70%	66.70%
Domestic defined benefit pension plans [Member] \| Debt Securities [Member]
Weighted-average asset allocations of domestic funded pension plans
Target asset allocation percentage	44.00%
Actual plan asset allocations	43.90%	27.80%
Domestic defined benefit pension plans [Member] \| Real Estate [Member]
Weighted-average asset allocations of domestic funded pension plans
Target asset allocation percentage	4.00%
Actual plan asset allocations	4.30%	5.40%
Domestic defined benefit pension plans [Member] \| Cash [Member]
Weighted-average asset allocations of domestic funded pension plans
Target asset allocation percentage	0.00%
Actual plan asset allocations	0.10%	0.10%
Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	15.8	447.8
Fair Value, Inputs, Level 1 [Member] \| Common Stock [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets

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- Definition

Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

+ 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 (b)

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

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 30

-Section 35

-Paragraph 50

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- Definition

Target allocation of investments of this type to total plan assets presented on a weighted average basis.

+ 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 (d)(i)

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

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- Definition

Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 5

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e2446-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

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