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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.

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- Definition

Summary of significant accounting policies.

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