INCOME TAXES - Components of loss (income) before income taxes (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2024	Sep. 30, 2023
Income Tax Disclosure [Abstract]
U.S.	$ (135,913)	$ (121,245)
Non-U.S.	5,153	(2,997)
Loss before income taxes	$ (130,760)	$ (124,242)

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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+ Details