Employee Benefit Plans (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Employee Benefit Plans (Textual) [Abstract]
Expenses related to savings plan	$ 24.8	$ 26.3	$ 27.9
Employee Benefit Plan obligations	20.1
Unfunded net pension	10.0
Percentage of minimum investment return	2.00%	2.00%	2.00%
Pension Expense	3.6	3.0	2.4
Savings plan [Member]
Employee Benefit Plans (Textual) [Abstract]
Minimum qualifying age for Employee Benefit Plan (in years)	21 years
Previous matching contributions vesting period (in years)	4 years
Supplemental savings plan [Member]
Employee Benefit Plans (Textual) [Abstract]
Deferred compensation related to Employee Benefit Plan	60.1	62.2
Deferred compensation plan [Member]
Employee Benefit Plans (Textual) [Abstract]
Previous Restoration Match vesting period (in years)	4 years
Previous transition contributions vesting period (in years)	7 years
German plan [Member]
Employee Benefit Plans (Textual) [Abstract]
Employee Benefit Plan obligations	8.6	8.2
Periodic pension cost	$ 1.8	$ 1.1	$ 1.1

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Minimum qualifying age for employee benefit plan.

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- Definition

Percentage of minimum investment return.

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No definition available.

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- Definition

Previous matching contributions vesting period.

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No definition available.

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- Definition

Previous restoration match vesting period.

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- Definition

Previous transition contributions vesting period.

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No definition available.

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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable beyond one year (or the operating cycle, if longer).

+ References

No definition available.

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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

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Projected Benefit Obligation

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-Glossary Accumulated Postretirement Benefit Obligation

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- Definition

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

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.

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- Definition

The amount of the cost recognized during the period for defined contribution plans.

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The amount of pension benefit costs recognized during the period for (1) defined benefit plans and (2) defined contribution plans. For defined benefit plans, pension expense includes the following components: service cost, interest cost, expected return on plan assets, gain (loss) on plan assets, prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments. For defined contribution plans, the pension expense generally equals the firm's contribution to employees' accounts (if the firm contributes) during the period.

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