Benefit Plans (Summary Of Stock Option And SAR Transactions) (Details) (USD $)	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010
Benefit Plans [Abstract]
Number of Awards Outstanding, January 1	6,104,501	5,657,996
Number of Awards, Granted	910,200	962,850
Number of Awards, Exercised	(370,789)	(500,658)
Number of Awards, Canceled	(19,303)	(15,687)
Number of Awards Outstanding, December 31	6,624,609	6,104,501
Awards exercisable, December 31	4,599,587	3,965,726
Weighted Average Exercise Price Awards outstanding, January 1	$ 33.082	$ 31.242
Weighted Average Exercise Price, Granted	$ 39.957	$ 36.544
Weighted Average Exercise Price, Exercised	$ 25.502	$ 19.860
Weighted Average Exercise Price, Canceled	$ 34.692	$ 35.055
Weighted Average Exercise Price Awards outstanding, December 31	$ 34.447	$ 33.082
Weighted Average Exercise Price exercisable, December 31	$ 33.405	$ 31.501

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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 weighted average price at which option holders acquired shares when converting their stock options into shares under the plan during the reporting period.

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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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The combined weighted average exercise price associated with stock options during the period that have either lapsed or been forfeited.

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

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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 stock options awarded under the plan during the reporting 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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The weighted average price as of the beginning of the year at which grantees can acquire the shares reserved for issuance under the stock option plan.

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

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