Property and Equipment - Summary of Property and Equipment (Detail) - USD ($)	Mar. 31, 2019	Sep. 30, 2018
Property Plant And Equipment [Abstract]
Computers, office equipment and furniture	$ 588,044	$ 600,334
Research equipment	11,021,467	10,751,627
Software	145,802	152,676
Leasehold improvements	12,469,048	12,236,150
Total gross fixed assets	24,224,361	23,740,787
Less: Accumulated depreciation and amortization	(10,846,040)	(9,805,362)
Property and equipment, net	$ 13,378,321	$ 13,935,425

Research equipment gross.

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- Definition

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