Employee Retirement Plans (Reconciliation of Projected Benefit Obligation, Fair Value of Plan Assets, and Funded Status) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Changes in plan assets
Fair value of plan assets, end of year	$ 548.6	$ 525.2
Pension Plans, Defined Benefit [Member]
Changes in benefit obligation
Projected benefit obligation, beginning of year	635.2	744.0
Service cost	0	0
Interest cost	29.3	28.2
Plan participants contributions	0	0
Plan termination	0	0
Actuarial (gain) / loss	104.1	(78.5)
Benefits paid	(57.3)	(58.5)
Projected benefit obligation, end of year	711.3	635.2
Changes in plan assets
Fair value of plan assets, beginning of year	525.2	458.9
Actual return on plan assets	44.4	84.3
Employer contributions	36.3	40.5
Plan participants contributions	0	0
Benefits paid	(57.3)	(58.5)
Fair value of plan assets, end of year	548.6	525.2
Funded status
Funded status	(162.7)	(110.0)
Other Postretirement Benefit Plans, Defined Benefit [Member]
Changes in benefit obligation
Projected benefit obligation, beginning of year	4.0	5.4
Service cost	0	0
Interest cost	0.1	0.1
Plan participants contributions	0.1	0.2
Plan termination	(3.7)	0
Actuarial (gain) / loss	0	(1.0)
Benefits paid	(0.5)	(0.7)
Projected benefit obligation, end of year	0	4.0
Changes in plan assets
Fair value of plan assets, beginning of year	0	0
Actual return on plan assets	0	0
Employer contributions	0.4	0.5
Plan participants contributions	0.1	0.2
Benefits paid	(0.5)	(0.7)
Fair value of plan assets, end of year	0	0
Funded status
Funded status	$ 0	$ (4.0)

The difference between fair value of plan assets at the end of the period and the fair value at the beginning of the period, adjusted for contributions and payments of benefits during the period, and after adjusting for taxes and other expenses, as applicable.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Actual Return on Plan Assets (Component of Net Periodic Postretirement Benefit Cost)

-URI http://asc.fasb.org/extlink&oid=6504192

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

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-Section 50

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-Subparagraph (b)(1)

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Actual Return on Plan Assets (Component of Net Periodic Pension Cost)

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Amount of gain (loss) related to change in benefit obligation resulting from changes in actuarial assumptions, for example, but not limited to, interest, mortality, employee turnover, salary, and temporary deviation from the substantive plan.

+ References

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-Topic 715

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1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-Topic 715

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-Section 50

-Paragraph 1

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Projected Benefit Obligation

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Accumulated Postretirement Benefit Obligation

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The amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes payments made under a postretirement benefit plan, including prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. This item represents a periodic decrease to the plan obligations and a decrease to plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Postretirement Benefits

-URI http://asc.fasb.org/extlink&oid=6521376

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-Topic 715

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-Glossary Benefits

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- Definition

The increase in the fair value of plan assets from contributions made by the employer.

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The amount of contributions made by plan participants. This item represents a periodic increase to the plan obligation and an increase to plan assets.

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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.

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The funded status is measured as the difference between the fair value of plan assets and the benefit obligation. Will normally be the same as the net Defined Benefit Plan, Amounts Recognized in Balance Sheet, Total.

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The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

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The amount of increase or decrease due to a change in the terms of an existing plan or the initiation of a new plan. A plan amendment may increase or decrease benefits, including those attributed to years of service already rendered.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 60

-Glossary Plan Amendment

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The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

+ References

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