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Pension and Savings Plans (Details 5) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2016 | Dec. 31, 2015
Corporate Debt Securities [Member] |  |
Summary of changes in the fair value of the Master Trust's investments |  |
Fair value of plan assets at beginning of period | $ 259.4 |
Assets Held At Reporting Date: |  |
Fair value of plan assets at end of period | $ 265.7 | $ 259.4
Real Estate [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target allocations for assets of Master Trust | 2.00% | 3.00%
Equity Securities [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target allocations for assets of Master Trust |  | 31.00%
Fixed Income Investments [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target allocations for assets of Master Trust |  | 69.00%
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 | $ 23.0 |
Assets Held At Reporting Date: |  |
Fair value of plan assets at end of period | 14.1 | $ 23.0
Private Equity Funds [Member] |  |
Summary of changes in the fair value of the Master Trust's investments |  |
Fair value of plan assets at beginning of period | 183.9 |
Assets Held At Reporting Date: |  |
Fair value of plan assets at end of period | 186.1 | 183.9
Banks, Trust and Insurance, Equities [Member] |  |
Summary of changes in the fair value of the Master Trust's investments |  |
Fair value of plan assets at beginning of period | 97.3 |
Assets Held At Reporting Date: |  |
Fair value of plan assets at end of period | 109.0 | 97.3
Fair Value, Inputs, Level 2 [Member] |  |
Summary of changes in the fair value of the Master Trust's investments |  |
Fair value of plan assets at beginning of period | 301.0 |
Assets Held At Reporting Date: |  |
Fair value of plan assets at end of period | 301.0 | 301.0
Fair Value, Inputs, Level 2 [Member] | Corporate Debt Securities [Member] |  |
Summary of changes in the fair value of the Master Trust's investments |  |
Fair value of plan assets at beginning of period | 259.4 |
Assets Held At Reporting Date: |  |
Fair value of plan assets at end of period | 265.7 | 259.4
Fair Value, Inputs, Level 2 [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 | 0.0 |
Assets Held At Reporting Date: |  |
Fair value of plan assets at end of period | 0.0 | 0.0
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 | 23.0 |
Assets Held At Reporting Date: |  |
Fair value of plan assets at end of period | 14.1 | 23.0
Level 3 [Member] | Corporate Debt 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 | 23.0 | 30.2
Assets Held At Reporting Date: |  |
Realized gains | 1.8 | 3.2
Unrealized gains relatng to investments still held at the reporting date | 0.2 | 0.2
Purchases, sales and settlements, net | (10.9) | (10.6)
Fair value of plan assets at end of period | 14.1 | 23.0
Pension Plans, Defined Benefit [Member] |  |
Summary of changes in the fair value of the Master Trust's investments |  |
Fair value of plan assets at beginning of period | 757.3 | 839.8
Assets Held At Reporting Date: |  |
Fair value of plan assets at end of period | $ 773.0 | $ 757.3

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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 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 + Details
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