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NATURE OF OPERATIONS (Details) $ in Thousands | 1 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2019 USD ($) | Sep. 30, 2020 USD ($) location | Sep. 30, 2019 USD ($) | Sep. 30, 2018 USD ($)
Segment Reporting Information [Line Items] |  |  |  |
Number of international locations | location |  | 4 |  |
Proceeds from sale of subsidiary |  | $ 15,056 | $ 0 | $ 0
Gain on sale of subsidiary |  | $ 14,963 | $ 0 | $ 0
Disposal Group, Disposed of by Sale, Not Discontinued Operations | TerraVici |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Percent of outstanding capital stock transferred to the purchaser | 100.00% |  |  |
Proceeds from sale of subsidiary | $ 15,100 |  |  |
Gain on sale of subsidiary | $ 15,000 |  |  |

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