Pension and Savings Plans (Details 5) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Real Estate Investment [Member]
Summary of changes in the fair value of the Master Trust's investments
Fair value of plan assets at beginning of period	$ 29.9
Assets Held At Reporting Date:
Fair value of plan assets at end of period	30.2	$ 29.9
Level 3 [Member]
Summary of changes in the fair value of the Master Trust's investments
Fair value of plan assets at beginning of period	29.9
Assets Held At Reporting Date:
Fair value of plan assets at end of period	30.2	29.9
Level 3 [Member] \| Real Estate Investment [Member]
Summary of changes in the fair value of the Master Trust's investments
Fair value of plan assets at beginning of period	29.9	27.8
Assets Held At Reporting Date:
Realized gains	0.2	0.7
Unrealized gains relatng to investments still held at the reporting date	4.9	2.6
Purchases, sales and settlements, net	(4.8)	(1.2)
Fair value of plan assets at end of period	$ 30.2	$ 29.9

Assets held at the reporting date.

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- Definition

Defined benefit plan actual return on plan assets unrealized during period.

+ References

No definition available.

+ Details

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- Definition

Actual return on plan assets, separately identifying the amount related to assets still held at the reporting date.

+ 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)(iv)(02)(A)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)(iv)(02)(A)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920

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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.

+ References

No definition available.

+ Details

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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 30
-Section 35
-Paragraph 50
-URI http://asc.fasb.org/extlink&oid=49178875&loc=d3e12355-114930

Reference 2: 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=58740216&loc=d3e1928-114920

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- Definition

Amount of increase (decrease) in plan assets from purchases, sales and settlement of plan obligations.

+ 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)(iv)(02)(B)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)(iv)(02)(B)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920

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