NATURE OF OPERATIONS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Concentration of customer Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2023
Revenue, Major Customer [Line Items]
Revenue	$ 179,691	$ 172,083	$ 172,552
Accounts receivable, net	36,811	31,682	32,132
Customer Concentration Risk \| Sales Revenue Net
Revenue, Major Customer [Line Items]
Revenue	26,900	29,600	27,700
Customer Concentration Risk \| Accounts Receivable
Revenue, Major Customer [Line Items]
Accounts receivable, net	$ 3,800	$ 5,500	$ 2,700
Customer Concentration Risk \| Customer One \| Sales Revenue Net
Revenue, Major Customer [Line Items]
Concentration risk (as a percent)	15.00%	17.00%	16.00%
Geographic Concentration Risk \| Long-Term Assets \| International
Revenue, Major Customer [Line Items]
Concentration risk (as a percent)	78.00%	78.00%
Geographic Concentration Risk \| Long-term Assets, Excluding Goodwill and Other Intangibles \| International
Revenue, Major Customer [Line Items]
Concentration risk (as a percent)	17.00%	19.00%

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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