SEGMENT AND GEOGRAPHIC INFORMATION - Geographic Information (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Sep. 30, 2024
SEGMENT INFORMATION
Revenue	$ 119,876	$ 135,501
Long-lived assets	182,279		$ 188,328
United States
SEGMENT INFORMATION
Revenue	97,399	111,769
Long-lived assets	163,221		167,772
Netherlands
SEGMENT INFORMATION
Revenue	15,834	18,062
Long-lived assets	6,278		7,159
Other
SEGMENT INFORMATION
Revenue	6,643	$ 5,670
Long-lived assets	$ 12,780		$ 13,397

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