Additional PSUs

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- Definition

Closing stock price

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- Definition

Discount For The ESPP

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- Definition

Exercise Of Stock Options

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- Definition

Grants Received By Certain Executive Officers And a Select Group Of Non Officer Employees

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- Definition

Grants vest on anniversary if performance met, year

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- Definition

Grants vest on anniversary if performance not met, year

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- Definition

Percentage Of Target Amount Granted Maximum

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- Definition

Percentage Of Target Amount Granted Minimum

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- Definition

Performance Period Of Grants Received

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- Definition

Restricted stock vesting range, maximum

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- Definition

Restricted Stock Vesting Range Minimum

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- Definition

Stock Options Generally Expire

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- Definition

Total Number Of In The Money Stock Options Exercisable

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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

Aggregate number of common shares reserved for future issuance.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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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.

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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.

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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

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The total fair value of equity-based awards for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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The total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under the plan.

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Share-Based Compensation (Narrative) (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended					1 Months Ended	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011 years	Sep. 30, 2010	Sep. 30, 2011 Three Year Performance Period [Member] PSUs [Member] years	Sep. 30, 2011 One Year Performance Period [Member] PSUs [Member] years	Sep. 30, 2011 Deferred Compensation, Share-Based Payments [Member]	Feb. 28, 2011 PSUs [Member]	Sep. 30, 2011 PSUs [Member]	Sep. 30, 2011 Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Restricted stock vesting range, minimum (in years)			3
Restricted stock vesting range, maximum (in years)			5
Stock options generally expire, period in years			10
Grants vest on anniversary if performance met, year			fourth
Grants vest on anniversary if performance not met, year			fifth
Percentage of target amount granted, Minimum									0.00%
Percentage of target amount granted, Maximum									150.00%
Grants received by certain executive officers and a select group of non-officer employees					100,000	532,368			632,368
Performance period of grants received, years					3	1
Additional PSUs								19,142
Discount for the ESPP	15.00%	15.00%	15.00%	15.00%
Net cash proceeds from the exercise of stock options	$ 1	$ 1	$ 9	$ 3
Exercise of stock options	58,459	129,308	926,171	381,997
Closing stock price	$ 23.14		$ 23.14
Total number of in-the-money stock options exercisable	4,200,000		4,200,000
Weighted-average exercise price	$ 13.85	$ 10.99	$ 13.85	$ 10.99
Total fair value of stock options vested	1		2	1
Total pre-tax intrinsic value of stock options exercised	1	1	15	4
Total unrecognized compensation cost related to stock options							57			15
Weighted-average period unrecognized compensation cost is expected to be recognized, in years							1.9			1.7
Employee service share-based compensation, unrecognized compensation costs on nonvested awards							$ 57			$ 15
Common stock shares reserved for future issuance	6,100,000		6,100,000