Schedule of Financial Instruments Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Jun. 30, 2021	Sep. 30, 2020	Jun. 30, 2020
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Warrant liability	$ (19,768)	$ (22,355)
Level 3 | Fair Value, Measurements, Recurring [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Warrant liability	(19,768)	(22,355)	$ (27,259)	$ (40,483)
Total liability	$ (19,768)	$ (22,355)