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COMMITMENTS AND CONTINGENCIES (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2023
Loss Contingencies [Line Items] |  |  |
Purchase obligation, purchases during period | $ 218,603 | $ 159,362 | $ 184,422
Purchase obligation, due in next twelve months | 218,344 |  |
Purchase obligation due in second year | 789 |  |
Purchase obligation due in third year | 376 |  |
Purchase obligation due in fourth year | 218 |  |
Purchase obligation due in fifth year | 178 |  |
Purchase obligation, to be paid, after year five | $ 0 |  |
Peekskill, New York |  |  |
Loss Contingencies [Line Items] |  |  |
Site contingency, ownership period | 3 years |  |
Memphis, TN |  |  |
Loss Contingencies [Line Items] |  |  |
Site contingency, ownership period | 50 years |  |

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