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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 | 9 Months Ended
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Nov. 30, 2021 | Nov. 30, 2020 | Nov. 30, 2021 | Nov. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Number of shares repurchased | 851,100 | 1,175,800 | 3,602,800 | 1,691,300
Average Cost Per Share | $ 135.52 | $ 92.90 | $ 127.65 | $ 88.65
Available for repurchase, as of end of period | $ 876.2 | $ 1,402.4 | $ 876.2 | $ 1,402.4

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