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NATURE OF OPERATIONS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Concentration Of customer Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Mar. 31, 2025	Mar. 31, 2024	Sep. 30, 2024	Sep. 30, 2023
Revenue, Major Customer [Line Items]
Revenue	$ 51,929	$ 46,968	$ 89,183	$ 83,885
Accounts receivable, net	49,850	52,061	49,850	52,061	$ 31,682	$ 32,132
Customer Concentration Risk \| Sales Revenue Net
Revenue, Major Customer [Line Items]
Revenue	18,500	21,200	26,200	24,200
Customer Concentration Risk \| Accounts Receivable
Revenue, Major Customer [Line Items]
Accounts receivable, net	$ 13,200	$ 17,000	$ 13,200	$ 17,000
Customer Concentration Risk \| Customer One \| Sales Revenue Net
Revenue, Major Customer [Line Items]
Total revenue, percentage	21.00%	21.00%	19.00%	19.00%
Customer Concentration Risk \| Customer Two \| Sales Revenue Net
Revenue, Major Customer [Line Items]
Total revenue, percentage	15.00%	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			77.00%		78.00%
Geographic Concentration Risk \| Long-term Assets, Excluding Goodwill and Other Intangibles \| International
Revenue, Major Customer [Line Items]
Total revenue, percentage			13.00%		19.00%