Defined Benefit Plan, Fair Value of Plan Assets, Cash and Cash Equivalents

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- Definition

Defined Benefit Plan, Fair Value of Plan Assets, Debt Securities

+ References

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- Definition

Defined Benefit Plan, Fair Value of Plan Assets, Equity Securities

+ References

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- Definition

Defined Benefit Plan, Fair Value of Plan Assets, Other Investments

+ References

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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

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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Pension and Postretirement Benefits (Fair Value Measurements for Pension Plan Assets) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]
Total Equity Securities	$ 65.4
Total Debt Securities	255.2
Total Other Investments	49.5
Total Pension Plan Assets	371.7
Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Equity Securities		65.3
Total Debt Securities		236.8
Total Other Investments		46.1
Total Pension Plan Assets	371.7	349.1	361.4
Level 1 [Member] \| Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Equity Securities	65.4	65.3
Total Debt Securities	255.2	236.8
Total Pension Plan Assets	322.2	303.0
Level 2 [Member] \| Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Other Investments	49.5	46.1
Total Pension Plan Assets	49.5	46.1
Small/Mid Cap Equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Equity Securities	10.6
Small/Mid Cap Equity [Member] \| Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Equity Securities		10.5
Small/Mid Cap Equity [Member] \| Level 1 [Member] \| Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Equity Securities	10.6	10.5
Large Cap Equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Equity Securities	22.2
Large Cap Equity [Member] \| Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Equity Securities		20.8
Large Cap Equity [Member] \| Level 1 [Member] \| Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Equity Securities	22.2	20.8
International Equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Equity Securities	18.2
International Equity [Member] \| Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Equity Securities		20.3
International Equity [Member] \| Level 1 [Member] \| Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Equity Securities	18.2	20.3
Emerging markets equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Equity Securities	2.8
Emerging markets equity [Member] \| Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Equity Securities		3.2
Emerging markets equity [Member] \| Level 1 [Member] \| Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Equity Securities	2.8	3.2
SIIT dynamic equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Equity Securities	11.6
SIIT dynamic equity [Member] \| Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Equity Securities		10.5
SIIT dynamic equity [Member] \| Level 1 [Member] \| Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Equity Securities	11.6	10.5
Emerging Markets Debt [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Debt Securities	6.0
Emerging Markets Debt [Member] \| Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Debt Securities		6.6
Emerging Markets Debt [Member] \| Level 1 [Member] \| Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Debt Securities	6.0	6.6
High Yield Bond [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Debt Securities	6.5
High Yield Bond [Member] \| Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Debt Securities		6.9
High Yield Bond [Member] \| Level 1 [Member] \| Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Debt Securities	6.5	6.9
Long Duration Fund [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Debt Securities	242.7
Long Duration Fund [Member] \| Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Debt Securities		223.3
Long Duration Fund [Member] \| Level 1 [Member] \| Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Debt Securities	242.7	223.3
Cash [Member]
Defined Benefit Plan Disclosure [Line Items]
Cash	1.6
Cash [Member] \| Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Cash		0.9
Cash [Member] \| Level 1 [Member] \| Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Cash	1.6	0.9
Limited Partnership Interest [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Other Investments	26.3
Limited Partnership Interest [Member] \| Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Other Investments		23.5
Limited Partnership Interest [Member] \| Level 2 [Member] \| Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Other Investments	26.3	23.5
Common Collective Fund [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Other Investments	23.2
Common Collective Fund [Member] \| Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Other Investments		22.6
Common Collective Fund [Member] \| Level 2 [Member] \| Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Other Investments	$ 23.2	$ 22.6