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REVENUE CONCENTRATION - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2024	Mar. 31, 2023	Sep. 30, 2023	Sep. 30, 2022
Revenue, Major Customer [Line Items]
Revenue	$ 46,968	$ 46,123	$ 83,885	$ 91,826
Accounts receivable, net	52,061	47,869	52,061	47,869	$ 32,132	$ 35,922
Customer Concentration Risk \| Sales Revenue Net
Revenue, Major Customer [Line Items]
Revenue	21,200	12,600	24,200	27,500
Customer Concentration Risk \| Accounts Receivable
Revenue, Major Customer [Line Items]
Accounts receivable, net	$ 17,000	$ 9,400	$ 17,000	$ 9,400
Customer Concentration Risk \| Customer One \| Sales Revenue Net
Revenue, Major Customer [Line Items]
Total revenue, percentage	21.00%	16.00%	19.00%	15.00%
Customer Concentration Risk \| Customer Two \| Sales Revenue Net
Revenue, Major Customer [Line Items]
Total revenue, percentage	14.00%	11.00%	10.00%
Customer Concentration Risk \| Customer Three \| Sales Revenue Net
Revenue, Major Customer [Line Items]
Total revenue, percentage	11.00%
Geographic Concentration Risk \| Long-term Assets \| International
Revenue, Major Customer [Line Items]
Total revenue, percentage			71.00%		72.00%
Geographic Concentration Risk \| Long-term Assets, Excluding Goodwill and Other Intangibles \| International
Revenue, Major Customer [Line Items]
Total revenue, percentage			19.00%		23.00%