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Share-based payment, awards exercise, period maximum.

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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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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		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012 Y	Jun. 30, 2011	Dec. 31, 2011
Share-Based Compensation (Textual) [Abstract]
Total compensation cost related to nonvested awards, unrecognized	$ 25.7		$ 25.7		$ 15.9
Weighted-average period to recognize compensation cost (in years)			3
Aggregate intrinsic value for outstanding options and RSUs	89.1		89.1
Aggregate intrinsic value for vested options and RSUs	59.4		59.4
Weighted-average remaining contractual life for outstanding options and RSUs, in years			6
Weighted-average remaining contractual life for exercisable options and RSUs, in years			5
Share-based compensation			$ 5.1	$ 4.0
Outstanding options to purchase common shares not included in dilutive share	800,000	1,000,000	500,000	500,000
Share-based payment award granted minimum vesting period range			1 year
Share-based payment award granted maximum vesting period range			5 years
Share-based payment, awards exercise, period minimum			12 months
Share-based payment, awards exercise, period maximum			10 years
Stock Appreciation Right [Member]
Additional Share-based Compensation (Textual) [Abstract]
Granted, Shares			858,000
Restricted Stock Unit [Member]
Additional Share-based Compensation (Textual) [Abstract]
Granted, Shares			145,000