Employee Retirement Plans (Details 1) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Components of net retirement cost
Service cost	$ 0.8	$ 0.9	$ 3.0
Interest	19.6	18.7	19.7
Expected return on plan assets	(22.8)	(20.1)	(15.7)
Actuarial loss	1.8	1.9	4.2
Prior service cost	0.1	0.1	0.1
Other		0.2	(0.4)
Defined benefit expense	(0.5)	1.7	10.9
Profit sharing	9.3	8.3	7.6
Net expense	$ 8.8	$ 10.0	$ 18.5

Defined benefit plan costs other.

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- Definition

Defined benefit plans benefit obligation.

+ References

No definition available.

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- Definition

The net increase or decrease of changes in the value of either the benefit obligation or the plan assets resulting from experience different from that assumed or from a change in an actuarial assumption, or the consequence of a decision to temporarily deviate from the substantive plan.

+ References

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- Definition

The amount of the prior service cost or credit recognized in net periodic benefit cost relating to benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation.

+ References

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- Definition

An amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets.

+ References

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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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- Definition

The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

+ References

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- Definition

This element may be used to encapsulate any other periodic costs associated with defined benefit plans that are not separately disclosed.

+ References

No definition available.

+ Details

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- Definition

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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