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Revenue Recognition - Narrative (Details) - USD ($)	3 Months Ended		9 Months Ended
Revenue Recognition - Narrative (Details) - USD ($)	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Sep. 30, 2021
Disaggregation of Revenue [Line Items]
Revenue recognized included in contract liability balance at the beginning of the period	$ 1,100,000	$ 600,000	$ 11,100,000	$ 8,500,000
Impairment losses recognized on contract costs			$ 0	$ 0
Sales Revenue Net \| Transferred at Point in Time \| Product Concentration Risk
Disaggregation of Revenue [Line Items]
Total revenue, percentage	50.40%	53.40%	51.20%	48.90%
Selling and marketing
Disaggregation of Revenue [Line Items]
Contract costs included in selling and marketing expenses	$ 300,000	$ 300,000	$ 1,000,000	$ 800,000
Other Current and Non-current Assets
Disaggregation of Revenue [Line Items]
Contract costs	$ 2,400,000		$ 2,400,000		$ 2,300,000