Stockbased Compensation Expense (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Employee Service Share-based Compensation Aggregate Disclosures [Line Items]
Stock Option Awards	$ 48.7	$ 41.6	$ 35.6
Restricted Share/Unit Awards	33.1	25.4	20.8
Total Stock-based Compensation Expense	81.8	67.0	56.4
Excess income tax benefits from stock-based compensation plans recognized in equity	10.9	(1.6)	25.1
Stock Options
Employee Service Share-based Compensation Aggregate Disclosures [Line Items]
Typical vesting period for stock-based awards	3-5 years
Typical term of stock-based awards	7-10 years
Unrecognized Compensation Costs On Nonvested Awards	81
Unrecognized Compensation Costs On Nonvested Awards Weighted Average Period Of Recognition	2.7
Unrecognized Compensation Costs on Nonvested Awards, Latest Year of Recognition	2015
Restricted Shares/Units
Employee Service Share-based Compensation Aggregate Disclosures [Line Items]
Unrecognized Compensation Costs On Nonvested Awards	$ 44
Unrecognized Compensation Costs On Nonvested Awards Weighted Average Period Of Recognition	2.4
Unrecognized Compensation Costs on Nonvested Awards, Latest Year of Recognition	2015

Adjustment to additional paid in capital related to the net effect of excess tax benefits and tax deficiencies associated with an equity-based compensation plan other than an employee stock ownership plan (ESOP).

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The latest year through which unrecognized share-based compensation costs are expected to be reported.

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph h

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph h

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- Definition

The noncash expense that represents the cost of restricted stock distributed to employees as compensation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28

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The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock options, amortization of restricted stock, and adjustment for officers compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28

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Reflects the dating as to when the share-based award expires as specified in the award agreement, which may be presented in a variety of ways (for example, year, month and year, day, month and year, quarter of a year).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
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Description of the period of time over which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, which may be expressed in a variety of ways (for example, in years, month and year).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph a

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The noncash expense that accounts for the value of stock options distributed to employees as compensation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph 64

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-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph i

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