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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, 2018 | May 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Share-based compensation expense, before income taxes | $ 29,465 | $ 19,140
Stock options |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Share-based compensation expense, before income taxes | 11,115 | 10,370
Cash-settled restricted stock units (RSUs) |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Share-based compensation expense, before income taxes | 12,354 | 3,118
Stock-settled market stock units (MSUs) |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Share-based compensation expense, before income taxes | 4,636 | 3,621
Stock-settled performance stock units (PSUs) |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Share-based compensation expense, before income taxes | 406 | 1,353
Restricted stock awards (RSAs) |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Share-based compensation expense, before income taxes | 487 | 414
Employee stock purchase plan |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Share-based compensation expense, before income taxes | 467 | 264
Other share-based incentives |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Share-based compensation expense, before income taxes | $ 1,360 | $ 2,031

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- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.F) -URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5047-113901 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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