Share-Based Compensation (Summary Of Stock Option Plans) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Weighted Average price, Beginning of period	$ 10.97	$ 9.14	$ 7.55
Granted, Weighted Average price	$ 17.50	$ 16.11	$ 14.31
Cancelled, Weighted Average price	$ 14.53	$ 12.67	$ 9.27
Exercised, Weighted Average price	$ 7.81	$ 4.93	$ 7.10
Weighted Average price, End of period	$ 13.18	$ 10.97	$ 9.14
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Number of Shares, Beginning of period	2,912	3,002	3,077
Granted, Number of Shares	601	510	670
Cancelled, Number of Shares	(134)	(96)	(41)
Exercised, Number of Shares	(747)	(504)	(704)
Number of Shares, End of period	2,632	2,912	3,002

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.

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Weighted average price of options that were either forfeited or expired.

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

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

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-Publisher FASB

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-Paragraph A240

-Subparagraph b(1)(d)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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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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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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