License and Collaboration Agreements - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue	$ 124,926	$ 100,448
Collaborative Arrangement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Payment for option exercise	$ 237,000
Stock options exercised or expired	0
Development Milestone and Upfront Fee Recognized as Research and Development Expense	$ 14,000	8,500
Collaborative Arrangement \| Maximum [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Contingent research milestone payments	14,000
Development Milestone and Settlement Upfront Fee Recognized as Research and Development Expense	3,900,000
Collaborative Arrangement \| Roche
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue	22,000	13,200
Deferred Revenue	730,700
Deferred Revenue, Current	89,200
Deferred Revenue Separate Material Options Right	485,000
Research and development expense	13,400	$ 16,400
Collaboration Receivable	$ 15,100

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Deferred Revenue Separate Material Options Right.

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Development milestone and settlement upfront fee recognized as research and development expense.

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Milestone payment to be paid by company upon specified research milestone achievement.

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Payment for option exercise.

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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.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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Amount of deferred income and obligation to transfer product and service to customer for which consideration has been received or is receivable, classified as current.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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