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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of expense for research and development. Includes, but is not limited to, cost for computer software product to be sold, leased, or otherwise marketed and writeoff of research and development assets acquired in transaction other than business combination or joint venture formation or both. Excludes write-down of intangible asset acquired in business combination or from joint venture formation or both, used in research and development activity.

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Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 280
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Aggregate amount of development and regulatory milestones payable for each product or licensed service under agreement.

+ References

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- Definition

The amount of costs incurred related to the payment of specified development milestones under the agreement.

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The amount of milestone payments made to date under the terms of the agreement. May include payments for specified development and regulatory milestone payments.

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The number of initial licensed products or services for which the entity is obligated to pay specified amount per licensed product or service under the agreement.

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Collaboration and License Agreements - License Agreement (Details) $ in Thousands	1 Months Ended	12 Months Ended
	Aug. 31, 2016 USD ($) item shares	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Sep. 30, 2016 USD ($)
Agreements
Research and development		$ 41,211	$ 52,136
Accrued expenses for specified development milestones		4,899	4,867
License Agreement \| City of Hope
Agreements
Number of shares of common stock issued \| shares	24,019
Number of licensed products or services \| item	3
Specified development and regulatory milestone payments made to date		800
Costs incurred related to payment of specified development milestones		500	0
License Agreement \| City of Hope \| Maximum
Agreements
Development and regulatory milestones payable per product or licensed service	$ 10,300
License Agreement \| WuXi Biologics
Agreements
Development and regulatory milestones payable per product or licensed service				$ 25,800
Specified development and regulatory milestone payments made to date		5,800
Costs incurred related to payment of specified development milestones		4,000	$ 0
License Agreement \| WuXi Biologics \| Accrued expenses
Agreements
Accrued expenses for specified development milestones		$ 3,000