Stock Option Plan (Schedule Of Summary Of Stock Option Activity) (Details) (USD $)	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010
Stock Option Plan
Stock Option Outstanding, Beginning Balance	78,075
Stock Option, Granted
Stock Option, Exercised		0
Stock Option, Forfeited/Expired	2,530
Stock Option Outstanding, Closing Balance	75,545	82,700
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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- Definition

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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-Paragraph A240
-Subparagraph b(1)(e)
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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.

+ References

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- Definition

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

+ References

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-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(1)(d)
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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(1)(d)
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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.

+ References

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(1)(a)
-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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Number of share options (or share units) exercised during the current period.

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