Pension and Savings Plans (Details 5) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Real Estate [Member]
Defined Benefit Plan Disclosure [Line Items]
Target allocations for assets of Master Trust	3.00%	4.00%
Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target allocations for assets of Master Trust	31.00%	35.00%
Summary of changes in the fair value of the Master Trust's investments
Fair value of plan assets at beginning of period	$ 190.3
Assets Held At Reporting Date:
Fair value of plan assets at end of period	$ 147.3	$ 190.3
Fixed Income Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Target allocations for assets of Master Trust	69.00%	65.00%
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	$ 30.2
Assets Held At Reporting Date:
Fair value of plan assets at end of period	23.0	$ 30.2
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	30.2
Assets Held At Reporting Date:
Fair value of plan assets at end of period	23.0	30.2
Level 3 [Member] \| Equity Securities [Member]
Summary of changes in the fair value of the Master Trust's investments
Fair value of plan assets at beginning of period	0.0
Assets Held At Reporting Date:
Fair value of plan assets at end of period	0.0	0.0
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	30.2	29.9
Assets Held At Reporting Date:
Realized gains	3.2	0.2
Unrealized gains relatng to investments still held at the reporting date	0.2	4.9
Purchases, sales and settlements, net	(10.6)	(4.8)
Fair value of plan assets at end of period	$ 23.0	$ 30.2

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.

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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

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-Publisher FASB
-Name Accounting Standards Codification
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-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.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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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

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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

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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 5
-Subparagraph (c)(i)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920

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