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Lessee, Operating Lease, Lease Not Yet Commenced, Tenant Improvements

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Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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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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Commitments and Contingencies - Narrative (Details) $ in Thousands		1 Months Ended		12 Months Ended
	Dec. 20, 2019 USD ($)	May 31, 2022 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2018 USD ($)	May 31, 2025 USD ($)	Nov. 30, 2022 USD ($)	Jun. 30, 2021 USD ($) ft²	Apr. 30, 2019 ft²
Loss Contingencies [Line Items]
Sublease income				$ 0	$ 398
Cash paid for amounts included in measurement of lease liabilities				2,300	2,500
Research and development				$ 44,830	$ 56,434
Harpoon \| Assignment and License Agreement
Loss Contingencies [Line Items]
Reimbursable legal costs	$ 75
Minimum annual royalties	$ 250
License agreement termination, prior written notice required	30 days
Upfront fee paid						$ 500
Adimab \| Development and Option Agreement
Loss Contingencies [Line Items]
Upfront fee paid			$ 100
Research and development			100
Upfront and final fee			200
Exercised option fee			500					$ 500
Adimab \| Development and Option Agreement \| Minimum
Loss Contingencies [Line Items]
Research program milestone fees			150					500
Exercised option milestone fee			1,000					1,000
Adimab \| Development and Option Agreement \| Maximum
Loss Contingencies [Line Items]
Research program milestone fees			200					1,500
Exercised option milestone fee			$ 4,000					$ 2,000
Lease commenced in April 2019
Loss Contingencies [Line Items]
Laboratory and office space to be rented (in sqft) \| ft²										9,949
Sublease Agreement, Year One
Loss Contingencies [Line Items]
Sublease income		$ 2,100
Lease commencing June 2021
Loss Contingencies [Line Items]
Laboratory and office space to be rented (in sqft) \| ft²									25,778
Tenant improvements									$ 5,700
Security deposit provided							$ 700		$ 1,000