Stock-Based Compensation (Number And Weighted Average Exercise Price Of Stock Options Outstanding) (Details) (USD $)	3 Months Ended
Mar. 31, 2013
Stock-Based Compensation [Abstract]
Shares Under Stock Options, OUTSTANDING AT DECEMBER 31, 2011	640,454
Granted at market price, Shares Under Stock Options
Exercised, Shares Under Stock Options
Expired, forfeited, cancelled or repurchased, Shares Under Stock Options	(39,427)
Shares Under Stock Options, OUTSTANDING AT DECEMBER 31, 2012	601,027
Weighted Average Price Per Share OUTSTANDING AT DECEMBER 31, 2011	$ 18.70
Granted at market price, Weighted Average Price Per Share
Exercised, Weighted Average Price Per Share
Expired, forfeited, cancelled or repurchased, Weighted Average Price Per Share	$ 17.38
Weighted Average Price Per Share OUTSTANDING AT DECEMBER 31, 2012	$ 18.80

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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

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

+ References

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-Name Accounting Standards Codification

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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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No definition available.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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

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