Maximum range number of shares approved, net of any subsequent amendments and adjustments, for awards under share-based compensation plans.

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- Details

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- Definition

Maximum range number of shares approved subsequent to period end, net of any subsequent amendments and adjustments, for awards under share-based compensation plans.

+ Details

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- Definition

Represents the expense recognized during the period arising from share-based compensation arrangements (for example, shares of stock, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph 64

-Subparagraph b

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph g(1)

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

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- Definition

The total recognized tax benefit related to compensation cost for share-based payment arrangements recognized in income during the period.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph g(1)

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- Definition

The number of shares issuable under a share-based award plan pertaining to grants made during the period on other than stock option plans (for example, phantom stock plan, stock appreciation rights plan, performance target plan).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(2)(c)

+ Details

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- Definition

The weighted average fair value at grant for nonvested share-based awards issued during the period on other than stock option plans (for example, phantom stock plan, stock appreciation rights plan, performance target plan).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(2)(c)

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph c(1)

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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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Stock-Based Compensation (Details) (USD $) In Millions, except Share data	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Apr. 26, 2011
Stock-Based Compensation [Abstract]
Stock-Based Compensation Expense	$ 15	$ 13	$ 43	$ 40
Tax Benefit Recognized	$ (5)	$ (5)	$ (15)	$ (14)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Option and Restricted Stock Plan common stock authorized for issuance under the plan (in shares)					24,000,000
April 26, 2011 approved Stock Option and Restricted Stock Plan common stock authorized for issuance under the plan (in shares)					31,000,000
Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted Stock (in shares)			985,503
Weighted Average Fair Value of Restricted Stock (in dollars per share)			$ 30.18
Shares of Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted Stock (in shares)			403,097
Weighted Average Fair Value of Restricted Stock (in dollars per share)			$ 90.34