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Collaboration Agreements, License Agreement and Revenues - Summary of Revenue Recognized Under the Collaboration Agreements - Additional Information 4 (Detail) - USD ($)	3 Months Ended	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2022
Europe [Member]
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Remainder of transaction price, variable consideration from estimated future co-development billing		$ 7,600,000
Europe [Member] | Astellas Agreement [Member]
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Changes in revenue from changes to estimated variable consideration	$ 0
U.S./RoW and China [Member]
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Remainder of transaction price, variable consideration from estimated future co-development billing		18,000,000.0
Changes in revenue from changes to estimated variable consideration		$ 0

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- Definition

Variable consideration payment received from estimated future co-development billing.

+ References

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- Definition

Amount of revenue recognized arising from contract liability from change in timeframe for performance obligation to be satisfied.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (e)
-URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130551-203045

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- Definition

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+ References

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