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Stock and Stock-Based Incentive Plans Stock and Stock-Based Incentive Plans (Schedule of Common Stock Repurchases) (Details) - Share Repurchase Program - USD ($) $ / shares in Units, $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Aug. 31, 2017 | Aug. 31, 2016 | Aug. 31, 2017 | Aug. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Treasury Stock, Shares, Acquired | 2,453,100 | 2,365,200 | 5,487,800 | 4,934,700
Treasury Stock Acquired, Average Cost Per Share | $ 63.78 | $ 53.18 | $ 61.69 | $ 52.25
Available for repurchase, as of end of period | $ 1,251.8 | $ 1,890.2 | $ 1,251.8 | $ 1,890.2

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- Definition Amount remaining of a stock repurchase plan authorized. + References No definition available. + Details
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- Definition Total cost of shares repurchased divided by the total number of shares repurchased. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655 + Details
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