Stock-Based Compensation and Directors Stock Purchase Plan (Summary Of Option Activity) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term	0 years 2 months
Stock Options [Roll Forward]
Outstanding, Shares, Beginning Balance	474,894
Granted, Shares	0
Forfeited, Shares	0
Expired, Shares	(1,462)
Exercised, Shares	(404,757)
Outstanding, Shares, Ending Balance	68,675
Stock Options, Weighted Average Exercise Price [Roll Forward]
Outstanding, Weighted Average Exercise Price, Beginning Balance	$ 29.10
Granted, Weighted Average Exercise Price	$ 0.00
Forfeited, Weighted Average Exercise Price	$ 0.00
Expired, Weighted Average Exercise Price	$ 29.22
Exercised, Weighted Average Exercise Price	$ 29.07
Outstanding, Weighted Average Exercise Price, Ending Balance	$ 29.27
Outstanding, Aggregate Intrinsic Value, Ending Balance	$ 977

Share Based Compensation Arrangements By Share Based Payment Award Options Outstanding Aggregate Intrinsic Value

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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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.

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

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Number of options outstanding, including both vested and non-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 remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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 could have acquired the underlying shares with respect to stock options of the plan that expired.

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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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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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

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