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COMMITMENTS AND CONTINGENCIES (Details) - USD ($) $ in Millions | Mar. 31, 2020 | Sep. 30, 2019
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Loss Contingencies [Line Items] |  |
Purchase commitments for equipment, parts and supplies | $ 12.7 |
HPIDC Employee Injury Lawsuit |  |
Loss Contingencies [Line Items] |  |
Accrual for lawsuit settlement |  | $ 9.5

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- Details
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