Stock-Based Compensation (Summary Of Stock Options) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2013
Stock-Based Compensation [Abstract]
Number of Options, Outstanding, Beginning balance	4,240
Number of Options, Granted	348
Number of Options, Exercised	(234)
Number of Options, Forfeited or expired	(55)
Number of Options, Outstanding, Ending balance	4,299
Number of Options, Exercisable as of March 31, 2013	3,422
Weighted-Average Exercise Price, Outstanding, Beginning balance	$ 19.88
Weighted-Average Exercise Price, Granted	$ 17.37
Weighted-Average Exercise Price, Exercised	$ 14.22
Weighted-Average Exercise Price, Forfeited or expired	$ 20.58
Weighted-Average Exercise Price, Outstanding, Ending Balance	$ 19.97
Weighted-Average Exercise Price, Exercisable, Ending Balance	$ 20.69
Weighted-Average Remaining Contractual Term (Years), Outstanding	5 years 7 days
Weighted-Average Remaining Contractual Term (Years), Exercisable	4 years 11 days
Aggregate Intrinsic Value, Outstanding	$ 3,798
Aggregate Intrinsic Value, Exercisable	$ 2,896

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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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.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of options outstanding.

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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 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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Amount of difference between fair value of the underlying shares reserved for issuance and exercise prices of fully vested and expected to vest options outstanding.

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

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

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