The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Intangible Assets - Additional Information (Detail) - USD ($)	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Finite Lived Intangible Assets [Line Items]
Amortization expense	$ 1,700,429	$ 1,700,430	$ 1,700,429
Amortization of license agreements remainder of fiscal year 2021	1,700,429
Amortization of license agreements in 2022	1,700,429
Amortization of license agreements in 2023	1,700,429
Amortization of license agreements in 2024	1,700,429
Amortization of license agreements in 2025	1,700,429
Amortization of license agreements, thereafter	$ 6,861,006
Novartis \| Licensing Agreement
Finite Lived Intangible Assets [Line Items]
Amortization period of intangible assets	21 years
Finite-lived intangible assets, accumulated amortization	$ 828,596
Novartis \| Patents
Finite Lived Intangible Assets [Line Items]
Amortization period of intangible assets	14 years
Finite-lived intangible assets, accumulated amortization	$ 8,665,466