Goodwill and Intangible Assets - Summary of Intangible Assets Balances (Detail) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Acquired Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 1,240	$ 1,240
Accumulated amortization	(933)	(732)
Net book value	$ 307	$ 508
Developed Technology [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Useful life in years	6 years	6 years
Gross carrying amount	$ 1,220	$ 1,220
Accumulated amortization	(913)	(712)
Net book value	$ 307	$ 508
Tradenames & Trademarks [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Useful life in years	2 years	2 years
Gross carrying amount	$ 20	$ 20
Accumulated amortization	$ (20)	$ (20)