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Collaboration Agreements - Summary of Revenue Recognized Under the Collaboration Agreements - Additional Information 4 (Detail) $ in Millions | 3 Months Ended
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Mar. 31, 2019 USD ($)
Japan [Member] |
Revenue Recognition, Multiple-deliverable Arrangements [Line Items] |
Remainder of transaction price, variable consideration from estimated future co-development billing | $ 0.9
Europe [Member] |
Revenue Recognition, Multiple-deliverable Arrangements [Line Items] |
Remainder of transaction price, variable consideration from estimated future co-development billing | 12.7
Europe [Member] | Astellas Agreement [Member] |
Revenue Recognition, Multiple-deliverable Arrangements [Line Items] |
Changes in revenue due to prior period adjustment of performance obligations | 0.1
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 | 172.3
U.S./RoW and China [Member] | AstraZeneca Agreements [Member] |
Revenue Recognition, Multiple-deliverable Arrangements [Line Items] |
Changes in revenue due to prior period adjustment of performance obligations | $ 0.9

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- Definition Variable consideration payment received from estimated future co-development billing. + References No definition available. + Details
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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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130551-203045 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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- Details
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Period Type: |

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- Details
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- Details
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- Details
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