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Collaboration Agreements - Additional Information (Details)			1 Months Ended			3 Months Ended
	Aug. 17, 2021 USD ($)	Jul. 01, 2021 USD ($)	Jan. 31, 2022 USD ($)	Jan. 31, 2018 USD ($)	Oct. 31, 2017 USD ($)	Mar. 31, 2022 USD ($)	Mar. 31, 2021 USD ($)
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Deferred revenue						$ 486,700,000
Research and development expense						$ 53,043,000	$ 45,733,000
Increase in expected cost percentage						2.00%
Reduced revenue						$ 1,800,000
GlaxoSmithKline plc
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Effective date of agreement	Aug. 17, 2021
Upfront payments		$ 700,000,000				$ 700,000,000
Upfront payment received	$ 500,000,000		$ 200,000,000
Percentage of development cost						0.60
Collaboration revenue						$ 21,200,000
Research and development expense						5,400,000
GlaxoSmithKline plc | Maximum
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Additional milestone payments per program related to initiation of certain clinical studies and regulatory approval						$ 1,500,000,000
Alector
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Percentage of development cost						0.40
AbbVie Biotechnology Limited
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Upfront payments					$ 205,000,000
Upfront payment received				$ 200,000,000	5,000,000
Exclusive option rights exercised for each program					250,000,000
Collaboration revenue						$ 3,300,000	4,100,000
Deferred revenue						114,100,000	$ 128,200,000
AbbVie Biotechnology Limited | Maximum
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Additional milestone payments per program related to initiation of certain clinical studies and regulatory approval					$ 242,800,000
Innovent
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration revenue						0
Development milestone						11,500,000
Sales milestone						$ 112,500,000

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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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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