Share Based Compensation (Summary Of Activity In Stock Option Plans) (Details) - $ / shares	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding Options, Exercised	(2,000)
Employee Stock Option and Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding Options, Beginning Balance	217,857	244,147
Outstanding Options, Granted	87,615	0
Outstanding Options, Exercised	(2,000)	0
Outstanding Options, Forfeited	0	0
Outstanding Options, Expired	0	0
Outstanding Options, Ending Balance	303,472	244,147
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Outstanding, Weighted-Average Exercise Price, Beginning Balance	$ 13.56	$ 14.05
Outstanding, Weighted-Average Exercise Price, Granted	26.01	0.00
Outstanding, Weighted-Average Exercise Price, Exercised	6.21	0
Outstanding, Weighted-Average Exercise Price, Forfeited	0	0
Outstanding, Weighted-Average Exercise Price, Expired	0.00	0
Outstanding, Weighted-Average Exercise Price, Ending Balance	$ 17.20	$ 14.05

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(4)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Net 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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-Publisher FASB
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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 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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