Property and Equipment - Summary of Property and Equipment (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Sep. 30, 2020
Property Plant And Equipment [Abstract]
Computers, office equipment and furniture	$ 1,661	$ 662
Research equipment	27,500	20,654
Software	509	631
Leasehold improvements	41,869	25,238
Total gross fixed assets	71,539	47,185
Less: Accumulated depreciation and amortization	(22,864)	(16,304)
Property and equipment, net	$ 48,675	$ 30,881

Research equipment gross.

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Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated amortization of capitalized costs for computer software, including but not limited to, acquired and internally developed computer software.

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Amount before accumulated depreciation of equipment commonly used in offices and stores that have no permanent connection to the structure of a building or utilities. Examples include, but are not limited to, desks, chairs, tables, and bookcases.

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Amount before accumulated depreciation of additions or improvements to assets held under a lease arrangement.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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