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- Definition

Employee Stock Purchase Plan, Maximum Number Of Shares That May Be Purchased By Eligible Participants

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- Definition

Share Based Compensation Arrangement By Employee Stock Purchase Plan Stock Purchases as Percentage Of Employee Compensation Maximum

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Exercisable Price Percentage Of Closing Price Of Another Class Of Stock

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Expiry Period From Date Of Grant

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Maximum Share Value Authorized For Purchase Under Employee Stock Purchase Plan

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- Definition

Face amount or stated value of common stock per share; generally not indicative of the fair market value per share.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 30
-Article 5

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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

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.

+ 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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

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.

+ References

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- Definition

The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

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-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 18
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-Publisher FASB
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- Definition

The cash inflow associated with the amount received from the stock plan during the period.

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-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

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- Definition

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
-Publisher FASB
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-Paragraph A240
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General descriptive information regarding an arrangement under which employees and directors receive: (a) awards of equity shares, equity share options, or other equity instruments; or (b) the entity incurs liabilities to them: (1) in amounts based, at least in part, on the price of the entity's shares or other equity instruments; or (2) that require or may require settlement by issuance of the entity's shares. Such an arrangement is usually provided to employees and directors to compensate them, provide performance incentives to them, and to attract or retain their services. May also include pertinent information particular to a plan that is not elsewhere specified in the taxonomy.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

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-SubTopic 10
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-Paragraph 2
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Stock-Based Compensation - Additional Information (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	6 Months Ended			6 Months Ended
	Jun. 30, 2011 Year Investment	Dec. 31, 2010	Jun. 30, 2011 2003 Long-Term Incentive Plan	Jun. 30, 2011 Stock Appreciation Rights Year	Jun. 30, 2011 Restricted Stock Units	Jun. 30, 2011 Restricted Stock Units Service Based Awards	Jun. 30, 2011 Restricted Stock Units Performance Based Awards	Jun. 30, 2011 Common Stock Equivalents	Jun. 30, 2011 Employee Stock Option	Jun. 30, 2010 Employee Stock Option	Jun. 30, 2011 Employee Stock Purchase Plan	Jun. 30, 2010 Employee Stock Purchase Plan
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Common stock available for stock-based compensation awards			6.4
Common stock available for stock-based compensation awards, par value	$ 0.0005	$ 0.0005	$ 0.0005
Vest ratably over				4Y		4Y	4Y
Total unrecognized stock-based compensation cost	$ 57.5
Expiration date				7Y
Total unrecognized stock-based compensation cost, period to be recognized	2.4			4
Share entitlement description					each RSU that vests entitles the awardee to one common share			each CSE entitles the holder to one common share
Directors' fees payable, percentage Board of Directors members can opt to receive in cash								50.00%
Cash received from option exercises									14.6	9.5
Percentage of employee's compensation, eligible employees may not exceed, when purchasing Common Stock through payroll deductions											10.00%
Amount of employee's compensation, eligible employees may not exceed, when purchasing Common Stock through payroll deductions											23,750
Price equals to closing price of Common Stock, percentage											95.00%
Shares available for purchase											1.4
Cash received from share purchases											$ 1.8	$ 1.5