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Share based compensation arrangement by share based payment award award vesting percentage.

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Share based compensation arrangement by share based payment award performance based units expected to vest outstanding number.

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Share Based Compensation Arrangements By Performance Based Units Maximum Range Of Vesting Provisions.

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Share Based Compensation Arrangements By Performance Based units Minimum Range Of Vesting Provisions.

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Represents the expense recognized during the period 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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-Publisher FASB

-Name Accounting Standards Codification

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-Section 50

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-Section F

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The amount of expense, net of income tax, recognized during the period 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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Unrecognized cost of unvested share-based compensation awards.

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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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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Period 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, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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).

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

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Stock-Based Compensation Plans (Information Regarding Restricted Shares) (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unearned compensation costs	$ 30.6	$ 31.5
Recognition of unearned compensation, (years)	1 year
Fair value of Restricted Shares vested	34.8	34.9	36.4
Stock-based compensation expense	42.7	35.8	35.4
Related income tax benefit	(14.6)	(12.3)	(12.0)
Net stock-based compensation expense	$ 28.1	$ 23.5	$ 23.4
Shares
Outstanding — beginning of year	2,020,678
Granted	734,187
Canceled	(788,468)
Canceled	(109,849)
Outstanding — ending of year	1,856,548	2,020,678
Weighted Average Grant-Date Fair Value
Outstanding — beginning of year	$ 44.68
Granted	$ 64.35
Vested	$ 44.10
Canceled	$ 51.63
Outstanding — ending of year	$ 52.29	$ 44.68
Restricted Stock \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
General expiration period, from date of grant or time of termination	3 years
General vesting period	3 years
Restricted Stock \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
General expiration period, from date of grant or time of termination	1 year
General vesting period	1 year
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
General vesting period	36 months
Period for achieving performance targets on performance based units (years)	3 years
Minimum range of vesting provisions	0
Maximum range of vesting provisions	1,580,000
Estimated vesting of shares based on performance shares	1,244,000
Shares
Outstanding — ending of year	811,000
Performance Shares \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage of grants, depending on achievement of specific performance targets	200.00%
Performance Shares \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage of grants, depending on achievement of specific performance targets	0.00%