Stock-Based Compensation (Details)	9 Months Ended
Sep. 30, 2011 Y Acquistion CounterParties Segment
Stock-Based Compensation
Vesting period, low end of range (in years)	1
Vesting period, high end of range (in years)	3
Expiration of annual grants (in years)	10
Retirement age eligibility for employees (in years)	55
Retirement eligibility for employees, minimum years of service required (in years)	5
Percent of stock-based compensation related to retiree-eligible population (as a percent)	28.00%
Number of shares available for grant	21,936,920

Percent of stock-based compensation related to retiree-eligible population.

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- Definition

The age at which employees of the entity are eligible for retirement, which combined with reaching years of service triggers expense recognition of share based compensation expense, in years.

+ Details

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- Definition

The number of years of service which combined with reaching eligible retirement age triggers expense recognition of share based compensation expense, in years.

+ Details

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- Definition

The period of time after the grant date at which share-based compensation awards expire, expressed in years.

+ Details

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- Definition

The vesting period for awards granted with the May 2005 annual grant and subsequent.

+ Details

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- Definition

The vesting period for awards under the entity's share based plans, prior to the May 2005 annual grant.

+ Details

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- Details

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- Definition

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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