Employee Benefit Plans, Share Based Compensation by Share Based Payment Award Types (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Share-based Compensation Expense by Award Type
Share-Based Compensation Expense	$ 222.2	$ 182.0	$ 139.7
Employee Benefit Textuals [Abstract]
Employee Contribution Matched in Percent	25.00%
Matching Contributions to Plan	16.3	13.2	11.9
Deferred Compensation Liability	9.3	8.1
Stock Options [Member]
Share-based Compensation Expense by Award Type
Share-Based Compensation Expense	76.2	81.5	81.2
Employee Benefit Textuals [Abstract]
Unrecognized Compensation Cost Related to Unvested Stock Options - Adjusted for Forfeitures	94.8
Weighted Average Period that Unrecognized Compensation Cost Will be Recognized (years)	2.3
Assumed Options [Member]
Share-based Compensation Expense by Award Type
Share-Based Compensation Expense	0	0.8	0
RSU's and PSA's
Share-based Compensation Expense by Award Type
Share-Based Compensation Expense	4.4	4.2	0
Employee Benefit Textuals [Abstract]
Unrecognized Compensation Cost Related to Unvested Stock Options - Adjusted for Forfeitures	247.4
Weighted Average Period that Unrecognized Compensation Cost Will be Recognized (years)	2.1
Assumed Restricted Stock Units [Member]
Share-based Compensation Expense by Award Type
Share-Based Compensation Expense	0	0.6	0
Employee Stock Purchase Plan [Member]
Share-based Compensation Expense by Award Type
Share-Based Compensation Expense	123.1	81.8	44.1
Other Acquisition Related Compensation [Member]
Share-based Compensation Expense by Award Type
Share-Based Compensation Expense	$ 18.5	$ 13.1	$ 14.4

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Employee contribution matched in percent.

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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable within one year (or the operating cycle, if longer). Represents currently earned compensation under compensation arrangements that is not actually paid until a later date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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- Definition

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

+ References

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- Definition

As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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- Definition

The weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, using a decimal to express in number of years.

+ References

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- Definition

Equity-based compensation cost during the period with respect to the award, which will be recognized in income (as well as the total recognized tax benefit) or capitalized as part of the cost of an asset.

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