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Stock and Stock-Based Incentive Plans Stock and Stock-Based Incentive Plans (Composition of Share-Based Compensation Expense - By Grant Type) (Details) - USD ($) $ in Thousands | 3 Months Ended
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May 31, 2021 | May 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Share-based compensation expense, before income taxes | $ 41,857 | $ 25,600
Stock options |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Share-based compensation expense, before income taxes | 11,821 | 11,619
Cash-settled restricted stock units (RSUs) |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Share-based compensation expense, before income taxes | 20,972 | 7,405
Stock-settled market stock units (MSUs) |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Share-based compensation expense, before income taxes | 4,845 | 5,846
Stock-settled performance stock units (PSUs) |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Share-based compensation expense, before income taxes | 3,394 | 153
Restricted Stock [Member] |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Share-based compensation expense, before income taxes | 42 | 34
Stock-settled deferred stock units (DSUs) |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Share-based compensation expense, before income taxes | 0 | 0
Employee stock purchase plan |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Share-based compensation expense, before income taxes | 783 | 543
Other share-based incentives |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Share-based compensation expense, before income taxes | $ 4,219 | $ 730

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