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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 20

-Section 50

-Paragraph 1

-Subparagraph (b)

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

Reference 2: 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=29635418&loc=d3e12355-114930

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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

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)(i)

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

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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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Employee Retirement Plans (Details 4) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]
Actual Allocation	100.00%
Fair Value Measurement	434.5	$ 399.2	$ 340.1
Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair Value Measurement	4.8	7.0
Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair Value Measurement	429.7	392.2
Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair Value Measurement	0	0
Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Actual Allocation	1.00%
Liability hedging portfolio
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	50.00%
Actual Allocation	47.00%
Growth portfolio
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	50.00%
Actual Allocation	52.00%
Temporary cash investments
Defined Benefit Plan Disclosure [Line Items]
Fair Value Measurement	4.8	7.0
Temporary cash investments \| Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair Value Measurement	4.8	7.0
Temporary cash investments \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair Value Measurement	0	0
Temporary cash investments \| Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair Value Measurement	0	0
Debt common trust funds
Defined Benefit Plan Disclosure [Line Items]
Fair Value Measurement	275.0	101.3
Debt common trust funds \| Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair Value Measurement	0	0
Debt common trust funds \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair Value Measurement	275.0	101.3
Debt common trust funds \| Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair Value Measurement	0	0
Equity common trust funds
Defined Benefit Plan Disclosure [Line Items]
Fair Value Measurement	154.7	290.9
Equity common trust funds \| Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair Value Measurement	0	0
Equity common trust funds \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair Value Measurement	154.7	290.9
Equity common trust funds \| Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair Value Measurement	0	$ 0