Share-Based Compensation (Summary Of Stock-Settled SARs Activity Under 2007 Plan) (Detail) (Stock-Settled SARs Activity, USD $)	9 Months Ended
Sep. 30, 2012
Stock-Settled SARs Activity
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares, Outstanding	927,225
Granted, Shares	370,720
Exercised, Shares	(2,764)
Expired or forfeited, Shares	(142,255)
Shares, Outstanding	1,152,926
Weighted-Average Exercise Price, Outstanding	$ 30.18
Granted, Weighted-Average Exercise Price	$ 29.59
Exercised, Weighted-Average Exercise Price	$ 28.01
Expired or forfeited, Weighted-Average Exercise Price	$ 32.26
Weighted-Average Exercise Price, Outstanding	$ 29.74

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For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

+ References

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- Definition

Weighted average price of options that were either forfeited or expired.

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- Definition

Net number of share options (or share units) granted during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

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-Subparagraph (c)(1)(iv)(1)

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-Publisher FASB

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-Paragraph A240

-Subparagraph b(1)(d)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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- Definition

The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

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No definition available.

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Weighted average price at which grantees can acquire the shares reserved for issuance on stock options awarded.

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No definition available.

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- Definition

Number of share options (or share units) exercised during the current period.

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