Collaborative Arrangement, Expected Development Cost Funds, Year One

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- Definition

Collaborative Arrangement, Expected Development Cost Funds, Year Two

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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.

+ References

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.

+ References

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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Amount of revenue from collaborative arrangement. Excludes revenue from contract with customer under Topic 606.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-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

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 3
-SubTopic 10
-Topic 808
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479428/808-10-45-3

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Collaborative and Other Relationships - Other Research and Discovery Arrangements and Funding Arrangements (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		6 Months Ended
	Mar. 31, 2026	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Collaborative arrangements and non-collaborative arrangement transactions
Research and development:		$ 529.6	$ 399.0	$ 1,068.6	$ 833.1
Reduction of research and development expense		25.0	50.0		100.0
Milestone Payment, Future Development
Collaborative arrangements and non-collaborative arrangement transactions
Estimated additional payments upon achievement of development and commercial milestones		250.0		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		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		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		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		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		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		50.0
Other research and discovery
Collaborative arrangements and non-collaborative arrangement transactions
Research and development:		4.0	$ 16.6	6.0	$ 17.3
Sobi
Collaborative arrangements and non-collaborative arrangement transactions
Revenue recognized		$ 13.3		$ 13.3
Alteogen Inc.
Collaborative arrangements and non-collaborative arrangement transactions
Estimated additional payments upon achievement of development and commercial milestones	$ 10.0
Upfront and milestone paymentsmade to collaborative partner	20.0
Alloy Therapeutics, Inc.
Collaborative arrangements and non-collaborative arrangement transactions
Upfront and milestone paymentsmade to collaborative partner	$ 12.0