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Related Party Transactions - Additional Information (Detail) | 3 Months Ended
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Dec. 31, 2018
Collaboration Agreement [Member] | Vertex Pharmaceuticals Inc [Member] | Minimum [Member] |
Related Party Transaction [Line Items] |
Voting interest Percentage | 10.00%

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- Definition Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 5A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=121559654&loc=SL6759159-111685 + Details
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- Details
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- Details
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- Details
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