Pension and Postretirement Plans Projected Benefit Obligation (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at December 31,	$ 355.5	$ 324.6
Pension Plans, Defined Benefit [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation at January 1,	569.2	526.1
Service cost	2.6	5.1	5.2
Interest Cost	21.3	24.8	26.8
Actuarial loss	30.6	60.2
Benefits paid	(38.8)	(47.0)
Retiree drug subsidy received	0	0
Early retiree subsidy received	0	0
Other	0	0
Benefit obligation at December 31,	584.9	569.2	526.1
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at January 1,	312.5	324.0
Actual return on plan assets	44.2	15.4
Employer contributions	25.9	20.1
Defined Benefit Plan, Gross Prescription Drug Subsidy Receipts Received	0	0
Early Retirement Subsidy Received or Refunded	0	0
Defined Benefit Plan, Benefits Paid	(38.8)	(47.0)
Fair value of plan assets at December 31,	343.8	312.5	324.0
Unfunded status	(241.1)	(256.7)
Other Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation at January 1,	164.9	163.5
Service cost	0.5	0.3	0.2
Interest Cost	5.6	7.1	8.0
Actuarial loss	2.2	13.8
Benefits paid	(26.0)	(27.2)
Retiree drug subsidy received	0.6	0.7
Early retiree subsidy received	(0.1)	1.9
Other	4.7	4.8
Benefit obligation at December 31,	152.4	164.9	163.5
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at January 1,	12.1	12.3
Actual return on plan assets	0.4	0.3
Employer contributions	24.7	24.1
Defined Benefit Plan, Gross Prescription Drug Subsidy Receipts Received	0.6	0.7
Early Retirement Subsidy Received or Refunded	(0.1)	1.9
Defined Benefit Plan, Benefits Paid	(26.0)	(27.2)
Fair value of plan assets at December 31,	11.7	12.1	12.3
Unfunded status	$ (140.7)	$ (152.8)

Early Retirement Subsidy Received or Refunded

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- Definition

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.

+ References

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-Publisher FASB

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

-URI http://asc.fasb.org/extlink&oid=6504226

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- Definition

Amount of gain (loss) from a decision to temporarily deviate from the substantive plan, or from a change in benefit obligation or plan asset value from changes in actuarial assumptions, for example, but not limited to, interest, mortality, employee turnover or salary scale.

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- Definition

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

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-Glossary Accumulated Postretirement Benefit Obligation

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-Glossary Projected Benefit Obligation

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- Definition

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.

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-Glossary Postretirement 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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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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- Definition

Amount of the period's gross receipts received from the prescription drug subsidy, which is to be used in the roll forward of the accumulated postretirement benefit obligation of an applicable postretirement benefit plan.

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- Definition

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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Amount of other defined benefit plan costs.

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No definition available.

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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.

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-Glossary Service Cost (Component of Net Periodic Pension Cost)

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