Maximum amount payable upon achievement of commercial milestones.

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Maximum amount payable upon achievement of certain development and regulatory milestone events.

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Amount of expense for research and development attributable to approval of a target pair selection.

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Amount of expense for research and development attributable to cost reimbursements.

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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, Contingencies, and Collaborations - Alphamab (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025	Jun. 30, 2024
Agreement
Research and development	$ 37,617	$ 61,289
Collaborative Agreement \| Alphamab
Agreement
Maximum amount payable upon achievement of development and regulatory milestones				$ 201,500
Maximum amount payable upon achievement of commercial milestones				$ 414,000
Research and development expense, cost reimbursements		$ 100
Research and development expense, approval of a target pair selection			$ 1,200
Research and development	$ 0