Share Repurchases (Schedule Of Company's Share Repurchases) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	9 Months Ended
Oct. 31, 2012	Oct. 31, 2011
Share Repurchases [Abstract]
Total Number of Shares Repurchased	70.9	92.4
Average Price Paid per Share	$ 65.69	$ 53.61
Total Investment	$ 4,656.6	$ 4,957.0

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

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