Stock-Based Compensation (Summary Of Option Activity) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	9 Months Ended
Sep. 30, 2013
Stock Options [Roll Forward]
Outstanding, Shares, Beginning Balance	768,773
Granted, shares	0
Foreited, shares	0
Expired, Shares	0
Exercised, Shares	(293,280)
Outstanding, Shares, Ending Balance	475,493
Outstanding, Weighted Average Exercise Price, Beginning Balance	$ 31.51
Granted, Weighted Average Exercise Price	$ 0.00
Forfeited, Weighted Average Exercise Price	$ 0.00
Expired, Weighted Average Exercise Price	$ 0.00
Exercised, Weighted Average Exercise Price	$ 30.57
Outstanding, Weighted Average Exercise Price, Ending Balance	$ 32.09
Outstanding, Weighted Average Remaining Contractual Term (in years)	1 year 0 months
Outstanding, Aggregate Intrinsic Value, Ending Balance	$ 5,573

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

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- Definition

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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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

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- Definition

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

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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.

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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- Definition

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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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

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- Definition

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 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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