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Collaboration Agreements and Revenues - Summary of Revenue Recognized Under the Collaboration Agreements - Additional Information 4 (Detail) | 12 Months Ended
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Dec. 31, 2020 USD ($)
Japan [Member] |
Revenue Recognition, Multiple-deliverable Arrangements [Line Items] |
Transaction price, variable consideration from estimated future co-development billing | $ 0
Japan [Member] | Astellas Agreement [Member] |
Revenue Recognition, Multiple-deliverable Arrangements [Line Items] |
Changes in revenue due to prior period adjustment of performance obligations | 15,100,000
Europe [Member] |
Revenue Recognition, Multiple-deliverable Arrangements [Line Items] |
Transaction price, variable consideration from estimated future co-development billing | 27,600,000
Europe [Member] | Astellas Agreement [Member] |
Revenue Recognition, Multiple-deliverable Arrangements [Line Items] |
Changes in revenue due to prior period adjustment of performance obligations | 1,500,000
U.S./RoW and China [Member] |
Revenue Recognition, Multiple-deliverable Arrangements [Line Items] |
Transaction price, variable consideration from estimated future co-development billing | 37,900,000
U.S./RoW and China [Member] | Astellas Agreement [Member] |
Revenue Recognition, Multiple-deliverable Arrangements [Line Items] |
Changes in revenue due to prior period adjustment of performance obligations | $ (2,900,000)

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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 http://asc.fasb.org/extlink&oid=121604090&loc=SL49130551-203045 + Details
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- Details
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- Details
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- Details
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- Details
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