Number of shares of common stock represented by each performance unit.

No definition available.

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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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- Definition

Aggregate unrecognized cost of share-based awards, other than options, made to employees under an equity-based compensation plan, that have yet to vest.

+ References

No definition available.

+ Details

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- Definition

Period 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, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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- Definition

The liabilities paid during the accounting period for equity-based compensation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)(2)

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

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph c(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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Share-Based Compensation - Liability-Classified Awards (Detail) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Value Creation Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Liability paid	$ 24,000,000	$ 0	$ 0
Outstanding liability	0
Performance-Based Unit Awards [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Liability paid	37,000,000	25,000,000	0
Outstanding liability	26,000,000
Number of shares of common stock represented by each performance unit	1
Total unrecognized compensation cost	19,000,000
Unrecognized compensation cost, weighted-average remaining period	1 year 9 months 19 days
Performance-Based Unit Awards [Member] \| Minimum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting period	2 years
Performance-Based Unit Awards [Member] \| Maximum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting period	3 years
Other Performance-Based Awards [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Liability paid	203,000,000	0	0
Outstanding liability	0
Total unrecognized compensation cost	$ 0