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STOCK-BASED COMPENSATION PLANS (Narrative) (Details) $ in Millions | 12 Months Ended
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Aug. 31, 2016 USD ($) Interval shares | Aug. 31, 2015 USD ($) shares | Aug. 31, 2014 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Stock-based compensation expense | $ | $ 26.4 | $ 23.5 | $ 18.1
Total unrecognized compensation cost | $ | $ 22.4 |  |
Period of unrecognized compensation to be recognized | 3 years |  |
Shares available for future grants | 9,394,846 |  |
Fair value of shares vested | $ | $ 21.3 | $ 10.2 | $ 10.0
Certain RSUs |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Period of unrecognized compensation to be recognized | 4 years |  |
Restricted stock units |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Restricted stock awards and performance stock units, granted, shares | 1,137,000 | 987,574 | 1,191,544
Restricted stock units | United States |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Award vesting frequency | Interval | 3 |  |
Vesting period | 3 years |  |
Restricted stock units | Non-U.S. |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Award vesting frequency | Interval | 3 |  |
Vesting period | 3 years |  |
Performance Awards |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Restricted stock awards and performance stock units, granted, shares | 540,295 | 462,496 | 450,233
Performance Awards | Minimum |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Payout percentage | 50.00% |  |
Performance Awards | Maximum |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Payout percentage | 200.00% |  |
Performance Awards | EBITDA |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Percentage that performance targets are weighted | 75.00% | 75.00% | 75.00%
Performance Awards | Relative total stockholder return |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Percentage that performance targets are weighted | 25.00% | 25.00% | 25.00%
Liability awards |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Restricted stock awards and performance stock units, granted, shares | 464,782 | 392,517 |
Equivalent number of awards outstanding | 871,182 |  |
Equivalent number of shares expected to vest | 829,343 |  |
Stock appreciation rights and stock options |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Stock appreciation rights and stock options, granted, number | 0 | 0 | 0
Equivalent shares of SARs outstanding | 358,994 |  |
Cash-settled stock appreciation rights |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Stock appreciation rights and stock options, granted, number | 0 | 0 | 59,399
Equivalent shares of SARs outstanding | 38,446 |  |
Equivalent number of shares expected to vest | 36,524 |  |
Vesting in two years |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Vesting percentage | 25.00% |  |
Vesting period | 2 years |  |
Vesting in three years |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Vesting percentage | 25.00% |  |
Vesting period | 3 years |  |
Vesting in four years |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Vesting percentage | 50.00% |  |
Vesting period | 4 years |  |
Employee stock purchase plan |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Shares available for future grants | 3,646,714 |  |
Maximum number of shares per employee | 400 |  |
Purchase discount from market price | 15.00% | 15.00% | 15.00%

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