Pensions and Postretirement Benefits (Details 12) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Change in plan assets
Fair value of plan assets at beginning of year	$ 3,375.9	$ 0
Gross benefits paid	(31.0)	(30.4)
Fair value of plan assets at end of year	3,488.4	3,375.9
Amounts recognized in the Balance Sheet Consist of:
Accumulated other comprehensive income (loss) before tax	1,675.7	1,326.6	1,392.5
Other Postretirement Benefit Plans Defined Benefit [Member]
Change in plan assets
Fair value of plan assets at beginning of year	0
Company contributions	31.0	30.4
Gross benefits paid	31.0	30.4
Fair value of plan assets at end of year	0	0
Funded Status (Underfunded)	(314.0)	(326.6)
Amounts recognized in the Balance Sheet Consist of:
Accrued expenses current liability	(27.8)	(29.7)
Pension obligation non-current liability	(286.2)	(296.9)
Net asset (liability) recognized	(314.0)	(326.6)
Accumulated other comprehensive income (loss) before tax	$ (20.3)	$ (22.0)

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- Definition

The pretax total of net gain (loss), prior service cost (credit), and transition assets (obligations), as well as minimum pension liability if still remaining, included in accumulated other comprehensive income associated with a defined benefit pension or other postretirement plan(s) because they have yet to be recognized as components of net periodic benefit cost.

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The aggregate net amount recognized in the balance sheet associated with the defined benefit plan(s). Will normally be the same as the Defined Benefit Plan, Funded Status of Plan, Total.

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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.

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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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For a classified balance sheet, the amount recognized in balance sheet as a current liability associated with an underfunded defined benefit plan.

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This represents the noncurrent liability for underfunded plans recognized in the balance sheet that is associated with the defined benefit pension plans and other postretirement defined benefit plans.

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