Additional Share Based Compensation.

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Share Based Compensation.

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Share-based payment awards, exercise period, maximum.

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Share-based payment awards, exercise period, minimum.

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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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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Diluted Earnings Per Share

-URI http://asc.fasb.org/extlink&oid=6510752

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-Name Accounting Standards Codification

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-Glossary Contingent Stock Agreement

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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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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.

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The maximum vesting term 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.

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The minimum vesting term 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.

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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 period between the balance sheet date and expiration for all vested portions of options outstanding and currently exercisable (or convertible) under the plan, which may be expressed in a decimal value for number of years.

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The total dollar difference between fair values of the underlying shares reserved for issuance and exercise prices pertaining to options outstanding under the plan as of the balance sheet date.

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As of the balance sheet date, the total dollar difference between fair values of the underlying shares reserved for issuance and exercise prices of fully vested and expected to vest options outstanding.

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The weighted-average period between the balance sheet date and expiration date for fully vested and expected to vest options outstanding, which may be expressed in a decimal value for number of years.

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Share-Based Compensation (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended			1 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011 Year	Sep. 30, 2010	Dec. 31, 2010	Apr. 30, 2011 Stock Appreciation Right [Member]	Apr. 30, 2011 Restricted Stock Unit [Member]
Additional Share-based Compensation (Textual) [Abstract]
Company granted, Units						1,029,000	126,000
Share-Based Compensation (Textual) [Abstract]
Total compensation cost related to nonvested awards, unrecognized	$ 15.8		$ 15.8		$ 6.9
Weighted-average period to recognize compensation cost (in years)			3
Aggregate intrinsic value for outstanding options, SARs, and RSUs	63.0		63.0
Aggregate intrinsic value for vested options, SARs and RSUs	44.1		44.1
Weighted-average remaining contractual life for outstanding options, SARs, and RSUs, (in years)			6
Weighted-average remaining contractual life for exercisable options, SARs and RSUs, (in years)			5
Share-based compensation			$ 5.8	$ 4.7
Share-based payment awards, exercise period, minimum			12 months
Share-based payment awards, exercise period, maximum			10 years
Share based payment award granted minimum vesting period range			1 year
Share based payment award granted maximum vesting period range			5 years
Outstanding options to purchase common stock not included in computation of diluted earnings per share	1,000,000	2,900,000	700,000	5,000,000