Commercial milestone payments.

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- Definition

Development and sales milestone payments.

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No definition available.

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- Definition

Milestone payments.

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No definition available.

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- Definition

Regulatory and development milestone payment.

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No definition available.

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- Definition

Research services agreement option to extend.

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- Definition

Research services.

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- Definition

Amount of revenue recognized that was previously reported as deferred or unearned revenue.

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- Definition

Cash received from licensees for license fees during the current period.

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- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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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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No definition available.

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Collaborations - Additional Information (Detail) - USD ($)	1 Months Ended		3 Months Ended		9 Months Ended
	Jan. 31, 2020	Dec. 31, 2018	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
License and collaboration revenue			$ 2,299,000	$ 893,000	$ 4,898,000	$ 18,917,000
Deferred revenue, recognized					1,600,000
License
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
License and collaboration revenue				32,000		15,100,000
License \| Transfer of Exclusive License and Related Know-How
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
License and collaboration revenue						15,000,000.0
Exclusive License
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
License and collaboration revenue						100,000
Collaboration
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
License and collaboration revenue			2,299,000	861,000	4,898,000	3,817,000
Collaboration \| Reimbursable Out-of-Pocket and Personnel Costs Incurred Related to Research Services
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
License and collaboration revenue			$ 2,300,000	$ 900,000	4,900,000	$ 3,800,000
ISU Abxis \| Amended and Restated License Agreement
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Regulatory and development milestone payment		$ 2,500,000			0
ISU Abxis \| Amended and Restated License Agreement \| Maximum
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Milestone payment		19,500,000			0
Commercial milestone payments		$ 17,000,000.0			0
Biogen
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
License and collaboration revenue					$ 0
Biogen \| License and Collaboration Agreement (the “Biogen Agreement”)
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Research services					30 months
Research services option to extend					12 months
Biogen \| Exclusive License
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Up-front payments received	$ 15,000,000.0
Biogen \| Exclusive License \| Maximum
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Development and sales milestone payments	$ 340,000,000.0