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Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020
Research and Development Expense |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Cost of collaboration revenue | $ 1.1 | $ 1.7 | $ 2.6 | $ 3.2

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- Definition Cost of collaboration revenue. + References No definition available. + Details
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- Definition Summary of significant accounting policies. + References No definition available. + Details
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- Details
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