Leases - Additional Information (Detail) $ in Millions	3 Months Ended	6 Months Ended
	Mar. 31, 2020 USD ($)	Mar. 31, 2020 USD ($)
Leases [Abstract]
Lease description		The Company leases facilities for research, office, manufacturing and warehousing.
Lease, existence of option to extend		true
Lease, option to extend		The Company’s leases include one or more options to renew and extend the lease term at the Company’s discretion. These renewal options are not included in right-of-use assets and lease liabilities as they are not reasonably certain of exercise.
Operating lease cost	$ 0.1	$ 0.3
Weighted average remaining lease term for operating leases	7 years 10 months 24 days	7 years 10 months 24 days
Weighted average discount rate used to determine operating lease liabilities	4.60%	4.60%