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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
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May 31, 2018 | May 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Number of shares repurchased | 3,307,600 | 3,034,700
Average Cost Per Share | $ 62.69 | $ 60.00
Available for repurchase, as of end of period | $ 809.5 | $ 1,408.3

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