Share Repurchase Program (Schedule Of Shares Repurchased) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	1 Months Ended	3 Months Ended	6 Months Ended	19 Months Ended
Aug. 08, 2012	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Aug. 08, 2012
Share Repurchase Program
Shares repurchased	3,340	4,518	3,301	6,288	5,912	25,500
Average price per share	$ 85.49	$ 97.47	$ 58.44	$ 94.52	$ 57.16	$ 72.78
Total investment	$ 285,521	$ 440,369	$ 192,901	$ 594,355	$ 337,912	$ 1,900,000

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the par value method.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

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