Stock Option Plan (Schedule Of Summary Of Stock Option Activity) (Details) (USD $)	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010
Stock Option Plan [Abstract]
Stock Option Outstanding, Beginning Balance	78,075
Stock Option, Granted
Stock Option, Exercised		0
Stock Option, Forfeited/Expired	3,505
Stock Option Outstanding, Closing Balance	74,570	82,175
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

Stock Option Plan [Abstract]

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The weighted average price at which option holders acquired shares when converting their stock options into shares under the plan during the reporting period.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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- Definition

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

The combined weighted average exercise price associated with stock options during the period that have either lapsed or been forfeited.

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- Definition

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

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- Definition

The weighted average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on stock options awarded under the plan during the reporting period.

+ References

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-Publisher FASB

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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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The weighted average price as of the beginning of the year at which grantees can acquire the shares reserved for issuance under the stock option plan.

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

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