Stock Option Plan (Schedule Of Summary Of Stock Option Activity) (Details) (USD $)	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011
Stock Option Plan [Abstract]
Stock Option Outstanding, Beginning Balance	74,020	75,895
Stock Option, Granted
Stock Option, Exercised
Stock Option, Forfeited/Expired	7,395
Stock Option Outstanding, Closing Balance	66,625	75,895
Weighted Average Exercise Price Per Share Outstanding, Beginning Balance	$ 74.96
Weighted Average Exercise Price Per Share, Granted
Weighted Average Exercise Price Per Share, Exercised
Weighted Average Exercise Price Per Share, Forfeited/Expired	$ 74.96
Weighted Average Exercise Price Per Share Outstanding, Closing Balance	$ 74.96

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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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-Number 123R

-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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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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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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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

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

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