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Significant Agreements - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended		6 Months Ended	9 Months Ended		12 Months Ended
	Jul. 31, 2020	Oct. 31, 2017	Sep. 30, 2023	Sep. 30, 2022	Jun. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2016	Mar. 31, 2023	Mar. 31, 2007
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Research and development expense			$ 39,087	$ 26,901		$ 107,906	$ 86,658
Allergan License Agreement Member | Vitae Pharmaceuticals Inc [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Potential milestone payments to be made		$ 99,000
Aggregate potential milestone payable		$ 70,000
License expiration year		10 years
Milestone Expenses Paid									$ 2,000
Development and regulaotry milestones Expenses									$ 8,000
UCB License Agreement [Member] | UCB Biopharma [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Potential milestone payments to be made								$ 119,500
Aggregate potential milestone payable								$ 250,000
License expiration year								10 years
Research and development expense	$ 6,000							$ 5,000
Milestone payment payable					$ 5,800
License Agreement [Member] | Bayer Pharma AG [Member] | Maximum [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Aggregate payment obligation										$ 150,000

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 808
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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-Topic 235
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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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