Share-Based Compensation (Details 3) (Nonvested stock awards, USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Nonvested stock awards
Nonvested Stock Shares
Nonvested at the beginning of the period (in shares)	4,868,017
Granted (in shares)	1,739,775
Vested (in shares)	(1,600,553)
Forfeited (in shares)	(93,159)
Nonvested at the end of the period (in shares)	4,914,080	4,868,017
Nonvested Stock Shares, Weighted Average Grant Date Fair Value
Nonvested at the beginning of the period (in dollars per share)	$ 31.52
Granted (in dollars per share)	$ 33.43
Vested (in dollars per share)	$ 27.89
Forfeited (in dollars per share)	$ 33.69
Nonvested at the end of the period (in dollars per share)	$ 33.34	$ 31.52
Compensation expense for continuing operations	$ 48.7	$ 45.4	$ 39.1
Compensation expense for discontinued operations	1.2	1.1	1.2
Related income tax benefit recognized	17.9	16.7	14.4
Remaining unamortized expense of nonvested stock expected to be recognized	107.2
Period for expense amortized	2 years 3 months 18 days
Total fair value of shares vested	$ 53.5	$ 52.5	$ 46.5
Shares expected to be repurchased from employees who elect to tender shares to cover minimum tax withholdings	670,000

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.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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

-Publisher FASB

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The total fair value of equity-based awards for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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- Definition

Represents the expense recognized during the period for continuing operations, arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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No definition available.

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Represents the expense recognized during the period for discontinued operations, arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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No definition available.

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Represents the number of shares expected to be repurchased from employees who elect to tender shares to satisfy the minimum tax withholding obligations of the Company with respect to vesting of the shares.

+ References

No definition available.

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