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Collaborative Arrangement, Expected Development Cost Funds, Year Two

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Collaborative Arrangements, Investments In Counterparty

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Estimated additional payments upon achievement of development and commercial milestones.

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Reduction Of Research And Development Expense

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Total upfront and milestone payments made to collaborative partner.

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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 808
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479402/808-10-50-1

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Amount of expense for research and development. Excludes cost for computer software product to be sold, leased, or otherwise marketed, writeoff of research and development assets acquired in transaction other than business combination or joint venture formation or both, and 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/2009/role/commonPracticeRef
-Topic 730
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482916/730-10-50-1

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Collaborative and Other Relationships - Other Research and Discovery Arrangements and Funding Arrangements (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Feb. 28, 2025	Feb. 11, 2025
Collaborative arrangements and non-collaborative arrangement transactions
Research and development:	$ 1,778.6	$ 1,980.3	$ 2,445.4
Reduction of research and development expense	200.0
Milestone Payment, Future Development
Collaborative arrangements and non-collaborative arrangement transactions
Estimated additional payments upon achievement of development and commercial milestones	250.0
Felzartamab And Izastobart/HIB210 \| Human Immunology Biosciences Pre-Existing In License Commitments \| Milestone Payment, One
Collaborative arrangements and non-collaborative arrangement transactions
Estimated additional payments upon achievement of development and commercial milestones	35.0
Felzartamab And Izastobart/HIB210 \| Human Immunology Biosciences Pre-Existing In License Commitments \| Milestone Payment, Two
Collaborative arrangements and non-collaborative arrangement transactions
Estimated additional payments upon achievement of development and commercial milestones	30.0
Felzartamab And Izastobart/HIB210 \| Human Immunology Biosciences Pre-Existing In License Commitments \| Milestone Payment, Future Development
Collaborative arrangements and non-collaborative arrangement transactions
Estimated additional payments upon achievement of development and commercial milestones	130.0
Felzartamab And Izastobart/HIB210 \| Human Immunology Biosciences Pre-Existing In License Commitments \| Milestone Payment, Regulatory
Collaborative arrangements and non-collaborative arrangement transactions
Estimated additional payments upon achievement of development and commercial milestones	230.0
Felzartamab And Izastobart/HIB210 \| Human Immunology Biosciences Pre-Existing In License Commitments \| Milestone Payment, Commercial
Collaborative arrangements and non-collaborative arrangement transactions
Estimated additional payments upon achievement of development and commercial milestones	640.0
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Collaborative arrangements and non-collaborative arrangement transactions
Expected receipts to co-fund development costs, current				$ 200.0
Expected receipts to co-fund development costs, noncurrent					$ 50.0
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement \| City Therapeutics, Inc.
Collaborative arrangements and non-collaborative arrangement transactions
Upfront and milestone payments made to collaborative partner	16.0
Collaborative arrangements, investments in counterparty	30.0
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement \| Milestone Payment, Research \| City Therapeutics, Inc.
Collaborative arrangements and non-collaborative arrangement transactions
Estimated additional payments upon achievement of development and commercial milestones	21.5
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement \| Milestone Payment, Developmental \| City Therapeutics, Inc.
Collaborative arrangements and non-collaborative arrangement transactions
Estimated additional payments upon achievement of development and commercial milestones	360.0
Collaborative Arrangement, Transaction with Party to Collaborative Arrangement \| Milestone Payment, Sales-Based \| City Therapeutics, Inc.
Collaborative arrangements and non-collaborative arrangement transactions
Estimated additional payments upon achievement of development and commercial milestones	625.0
Other research and discovery
Collaborative arrangements and non-collaborative arrangement transactions
Research and development:	$ 13.4	$ 54.0	$ 4.1