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COMMITMENTS AND CONTINGENCIES (Narrative) (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
May 31, 2015 | Aug. 31, 2016 | Aug. 31, 2015 | Aug. 31, 2014
Loss Contingencies [Line Items] |  |  |  |
Total rental expense |  | $ 40.7 | $ 52.8 | $ 46.8
Inventory items sold in th eoridinary course of business as a percentage of purchase obligations (percent) |  | 68.00% |  |
Benefit on contract termination | $ 45.5 |  |  |
Total environmental liabilities |  | $ 3.3 | 4.3 |
Long-term environmental liabilities |  | 2.1 | 2.4 |
CERCLA sites |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Total environmental liabilities |  | $ 0.7 | $ 1.0 |

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