Future contingent milestone payment receivable.

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- Definition

Number of additional collaboration target.

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Number of targets.

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Number of targets selected.

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- Definition

Right to expand the number of additional collaboration target.

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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.

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- Definition

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

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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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Cash received from collaborators during the current period.

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Research and Collaboration Agreements - Astellas Pharma Inc - Additional Information (Details) $ in Thousands		1 Months Ended
	Mar. 23, 2020 USD ($) Target	Oct. 31, 2017 USD ($)	Jun. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)	Sep. 29, 2017 USD ($) Target
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue			$ 161,650	$ 194,922
Astellas Pharma Inc.
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue			43,700
Amgen Inc \| EGFR Products
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue			19,600
Collaboration and License Agreement \| Astellas Pharma Inc.
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Number of targets selected \| Target	1
Number of additional collaboration target \| Target	3
Upfront payment received	$ 80,000
Deferred revenue			43,700	51,600
Amount due from agreement			1,000	800
Collaboration and License Agreement \| Astellas Pharma Inc. \| Additional Contingent Payments
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Contingent milestone payments receivable	$ 900,000
Collaboration and License Agreement \| Astellas Pharma Inc. \| Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Number of targets \| Target	4
Right to expand the number of additional collaboration target \| Target	5
Contingent milestone payments receivable	$ 1,600,000
Collaboration and License Agreement \| Astellas Pharma Inc. \| Minimum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Right to expand the number of additional collaboration target \| Target	3
Collaboration and License Agreement \| Amgen Inc
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Number of targets selected \| Target					1
Number of additional collaboration target \| Target					2
Upfront payment received		$ 40,000
Collaboration and License Agreement \| Amgen Inc \| EGFR Products
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue			$ 19,600	$ 21,800
Collaboration and License Agreement \| Amgen Inc \| Maximum \| EGFR Products
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Contingent milestone payments receivable					$ 460,000