Earnings Per Share (Narrative) (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
Earnings Per Share
Common stock repurchased, shares	3,340	4,518	3,301	6,288	5,912	25,500
Common stock repurchased, average price per share	$ 85.49	$ 97.47	$ 58.44	$ 94.52	$ 57.16	$ 72.78
Common stock repurchased, value	$ 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

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