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STOCK-BASED COMPENSATION PLANS (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
May 31, 2018 | May 31, 2017 | May 31, 2018 | May 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Expenses from stock modification and increase in value | $ (100) | $ 2,000 | $ 1,600 | $ 2,700
Stock-based compensation | $ 4,910 | $ 3,560 | $ 18,247 | $ 19,716
Equity method awards |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Number of shares granted |  |  | 1,216,000 | 916,000
Weighted average grant-date fair value |  |  | $ 20.69 | $ 16.04
Liability method awards |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Number of shares granted |  |  | 323,000 | 915,000
Equivalent shares outstanding | 769,287 |  | 769,287 |
Equivalent shares expected to vest | 733,000 |  | 733,000 |
Fiscal 2018 | Cliff vesting restricted stock units |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Vesting period in years |  |  |  |

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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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5047-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -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=115993241&loc=d3e301413-122809 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -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=109197908&loc=d3e5070-113901 + Details
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