Summary of Significant Accounting Policies (Details) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2020 USD ($)	Mar. 31, 2020 USD ($) Segment	Sep. 30, 2019 USD ($)
Deferred Offering Costs [Abstract]
Deferred offering costs	$ 0	$ 0	$ 2,600
Contract Liability [Abstract]
Beginning contract liability	7,736	4,880
Revenue recognized from contract liabilities included in the beginning balance	(3,946)	(4,101)
Increases due to cash received, net of amounts recognized in revenue during the period	9,681	12,692
Ending contract liability	$ 13,471	$ 13,471
Segment Information [Abstract]
Number of operating segments \| Segment		1
Timing of Revenue [Abstract]
Percentage on Timing of Revenue Recognition	100.00%	100.00%
Transferred at Point in Time [Member]
Timing of Revenue [Abstract]
Percentage on Timing of Revenue Recognition	96.90%	96.00%
Transferred over Time [Member]
Timing of Revenue [Abstract]
Percentage on Timing of Revenue Recognition	3.10%	4.00%
IPO [Member]
Deferred Offering Costs [Abstract]
Offering cost charged against additional paid-in capital		$ 5,500

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Specific incremental costs directly attributable to a proposed or actual offering of securities which are deferred at the end of the reporting period.

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