SEGMENT AND GEOGRAPHIC INFORMATION - Geographic Information (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2024	Sep. 30, 2023
SEGMENT INFORMATION
Revenue	$ 490,739	$ 572,425
Long-lived assets	188,328	191,068
United States
SEGMENT INFORMATION
Revenue	419,104	482,630
Long-lived assets	167,772	178,021
Netherlands
SEGMENT INFORMATION
Revenue	44,694	54,088
Long-lived assets	7,159	6,656
Other
SEGMENT INFORMATION
Revenue	26,941	35,707
Long-lived assets	$ 13,397	$ 6,391

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details