REVENUE RECOGNITION - Narrative (Details) - USD ($)	3 Months Ended		6 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2024	Mar. 31, 2023	Sep. 30, 2023
Disaggregation of Revenue [Line Items]
Revenue recognized included in contract liability balance at the beginning of the period	$ 4,600,000	$ 3,300,000	$ 13,700,000	$ 9,900,000
Unbilled receivables	10,700,000		10,700,000		$ 900,000
Allowance for credit losses	2,400,000		2,400,000		1,500,000
Amortization of costs capitalized to obtain revenue contracts			847,000	724,000
Impairment losses recognized on contract costs			0	0
Selling and marketing
Disaggregation of Revenue [Line Items]
Amortization of costs capitalized to obtain revenue contracts	400,000	$ 400,000	800,000	$ 700,000
Other Current and Non-current Assets
Disaggregation of Revenue [Line Items]
Contract costs	$ 2,400,000		$ 2,400,000		$ 2,600,000
Minimum
Disaggregation of Revenue [Line Items]
Estimated useful lives of intangible assets (in years)	3 years		3 years
Minimum | Software
Disaggregation of Revenue [Line Items]
Estimated useful lives of intangible assets (in years)	1 year		1 year
Maximum
Disaggregation of Revenue [Line Items]
Estimated useful lives of intangible assets (in years)	7 years		7 years
Maximum | Software
Disaggregation of Revenue [Line Items]
Estimated useful lives of intangible assets (in years)	3 years		3 years