Stockholders’ Equity And Stock-Based Compensation (Schedule Of Stock Option Plans) (Details) (Stock Options [Member], USD $)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares under option, Outstanding	1,317,216	2,334,448	5,567,254
Number of shares under option, Exercised	(237,146)	(932,895)	(2,291,757)
Number of shares under option, Cancelled	(26,945)	(84,337)	(941,049)
Number of shares under option, Granted	0	0	0
Number of shares under option, Outstanding	1,053,125	1,317,216	2,334,448
Weighted average exercise price, Outstanding	$ 18.07	$ 17.15	$ 17.95
Weighted average exercise price, Exercised	$ 16.59	$ 15.94	$ 17.55
Weighted average exercise price, Cancelled	$ 17.07	$ 16.23	$ 20.93
Weighted average exercise price, Outstanding	$ 18.44	$ 18.07	$ 17.15

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

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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 could have acquired the underlying shares with respect to stock options that were terminated.

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

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