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Intangible Assets - Additional Information (Detail) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Mar. 31, 2021 | Mar. 31, 2020 | Mar. 31, 2021 | Mar. 31, 2020
Finite Lived Intangible Assets [Line Items] |  |  |  |
Amortization expense | $ 400 | $ 400 | $ 850 | $ 900
Amortization of license agreements remainder of fiscal year 2021 | 900 |  | 900 |
Amortization of license agreements in 2022 | 1,700 |  | 1,700 |
Amortization of license agreements in 2023 | 1,700 |  | 1,700 |
Amortization of license agreements in 2024 | 1,700 |  | 1,700 |
Amortization of license agreements in 2025 | 1,700 |  | 1,700 |
Amortization of license agreements, thereafter | 6,800 |  | $ 6,800 |
Novartis | Licensing Agreement |  |  |  |
Finite Lived Intangible Assets [Line Items] |  |  |  |
Amortization period of intangible assets |  |  | 21 years |
Finite-lived intangible assets, accumulated amortization | 900 |  | $ 900 |
Novartis | Patents |  |  |  |
Finite Lived Intangible Assets [Line Items] |  |  |  |
Amortization period of intangible assets |  |  | 14 years |
Finite-lived intangible assets, accumulated amortization | $ 9,400 |  | $ 9,400 |

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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274 + Details
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- Definition Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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