Accrued expenses on funding commitment related to clinical research.

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Future Contingent Payment For Annual Worldwide Net Sales That Exceed $2.0 Billion

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Future Contingent Payment For Annual Worldwide Net Sales Up To $2.0 Billion

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Future Contingent Payment Threshold

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Percentage of royalties as per collaboration.

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Potential future milestone payments commitment to third party approximately.

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Royalties Payable Period, Post FDA Approval

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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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For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

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Amount of liability recognized arising from contingent consideration in a business combination.

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Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled within one year or the normal operating cycle, if longer.

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Amount of deferred tax liability attributable to taxable temporary differences from undistributed earnings of subsidiary and other recognized entity not within country of domicile. Includes, but is not limited to, other basis differences.

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Amount recognized for uncertainty in income taxes classified as current.

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Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

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Commitments and Contingencies (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Apr. 30, 2023	Dec. 31, 2024	Dec. 31, 2025	Jun. 30, 2025	Jul. 02, 2024	Dec. 31, 2023
Business Acquisition [Line Items]
Potential future milestone payments commitment, approximately		$ 3,800.0
Accrued expenses		21.7
Cancellable future commitments		509.2
Liabilities associated with uncertain tax positions		173.8
Contingent consideration obligations		291.2
2017 Tax Act
Business Acquisition [Line Items]
Transition toll tax liabilities		234.0				$ 419.5
Development Milestones
Business Acquisition [Line Items]
Potential future milestone payments commitment, approximately		500.0
Regulatory Milestones
Business Acquisition [Line Items]
Potential future milestone payments commitment, approximately		500.0
Commercial Milestones
Business Acquisition [Line Items]
Potential future milestone payments commitment, approximately		$ 2,800.0
Felzartamab And Izastobart/HIB210 \| Milestone Payment, One \| Forecast \| Human Immunology Biosciences Pre-Existing In License Commitments
Business Acquisition [Line Items]
Contingent consideration obligations				$ 35.0
Felzartamab And Izastobart/HIB210 \| Milestone Payment, Two \| Human Immunology Biosciences Pre-Existing In License Commitments
Business Acquisition [Line Items]
Contingent consideration obligations					$ 30.0
Felzartamab And Izastobart/HIB210 \| Milestone Payment, Future Development \| Human Immunology Biosciences Pre-Existing In License Commitments
Business Acquisition [Line Items]
Contingent consideration obligations					130.0
Felzartamab And Izastobart/HIB210 \| Milestone Payment, Regulatory \| Human Immunology Biosciences Pre-Existing In License Commitments
Business Acquisition [Line Items]
Contingent consideration obligations					230.0
Felzartamab And Izastobart/HIB210 \| Milestone Payment, Commercial \| Human Immunology Biosciences Pre-Existing In License Commitments
Business Acquisition [Line Items]
Contingent consideration obligations					640.0
Ionis Pharmaceuticals \| Minimum \| SPINRAZA
Business Acquisition [Line Items]
Percentage of royalties as per collaboration		11.00%
Ionis Pharmaceuticals \| Minimum \| QALSODY
Business Acquisition [Line Items]
Percentage of royalties as per collaboration	11.00%
Ionis Pharmaceuticals \| Maximum \| SPINRAZA
Business Acquisition [Line Items]
Percentage of royalties as per collaboration		15.00%
Ionis Pharmaceuticals \| Maximum \| QALSODY
Business Acquisition [Line Items]
Percentage of royalties as per collaboration	15.00%
Alkermes \| VUMERITY
Business Acquisition [Line Items]
Percentage of royalties as per collaboration		15.00%
Royalties payable period, post FDA approval		5 years
Aducanumab \| Forecast
Business Acquisition [Line Items]
Potential future milestone payments commitment, approximately			$ 73.6
TYSABRI
Business Acquisition [Line Items]
Future contingent payment for annual worldwide net sales up to threshold, percentage		18.00%
Future contingent payment threshold		$ 2,000.0
Future contingent payment for annual worldwide net sales that exceeding threshold, percentage		25.00%
Human Immunology Biosciences
Business Acquisition [Line Items]
Contingent consideration obligations					485.1
Range of outcomes, value, high					650.0
Contingent consideration obligations					279.3
Human Immunology Biosciences \| Maximum \| Phase 3 Clinical Trial, Felzartamab Two
Business Acquisition [Line Items]
Contingent consideration obligations					150.0
Human Immunology Biosciences \| Maximum \| Phase 3 Clinical Trial, Felzartamab One
Business Acquisition [Line Items]
Contingent consideration obligations					$ 150.0