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ACQUISITIONS (Details) - Schedule of Intangible Assets Acquired in Cornell Cookson Acquisition (Details) - USD ($) $ in Thousands | Jun. 04, 2018 | Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2016
--- | --- | --- | --- | ---
Business Acquisition [Line Items] |  |  |  |
Goodwill |  | $ 439,395 | $ 319,139 | $ 306,163
Cornell Cookson [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Goodwill | $ 42,883 |  |  |
Indefinite-lived intangibles | 53,500 |  |  |
Definite-lived intangibles | $ 14,100 |  |  |
Amortization Period (Years) | 12 years |  |  |
Total goodwill and intangible assets | $ 110,483 |  |  |

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