Employee Benefits And Stock-Based Compensation (Summary Of Stock Options Activity) (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 [Abstract]
Outstanding at beginning of period, Shares	1,120	3,387	6,920
Granted, Shares	0	0	788
Exercised, Shares	(660)	(1,473)	(3,094)
Forfeited, Shares	(38)	(749)	(1,188)
Expired, Shares	(1)	(45)	(39)
Outstanding at end of period, Shares	421	1,120	3,387
Exercisable at end of period, Shares	387	910	1,812
Expected to vest at end of period, Shares	32
Outstanding at beginning of period, Weighted-Average Exercise Price	$ 28.04	$ 27.36	$ 26.64
Granted, Weighted-Average Exercise Price	$ 0	$ 0	$ 24.53
Exercised, Weighted-Average Exercise Price	$ 27.34	$ 26.34	$ 23.69
Forfeited, Weighted-Average Exercise Price	$ 23.99	$ 26.53	$ 28.88
Expired, Weighted-Average Exercise Price	$ 8.07	$ 48.33	$ 87.00
Outstanding at end of period, Weighted-Average Exercise Price	$ 29.49	$ 28.04	$ 27.36
Exercisable at end of period, Weighted-Average Exercise Price	$ 30.17	$ 28.83	$ 28.98
Expected to vest at end of period, Weighted-Average Exercise Price	$ 21.66
Weighted-average fair value of options granted during the period	$ 0	$ 0.00	$ 7.14
Total intrinsic value of options exercised during the period	$ 9,157	$ 12,599	$ 22,125

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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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The total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under the plan.

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

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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.

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

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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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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As of the balance sheet date, the number of shares into which fully vested and expected to vest stock options outstanding can be converted under the option plan.

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As of the balance sheet date, the weighted-average exercise price for outstanding stock options that are fully vested or expected to vest.

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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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