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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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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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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

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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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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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Commitments and Contingencies (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2024	Jun. 30, 2022
Business Acquisition [Line Items]
Potential future milestone payments commitment, approximately		$ 5,100.0	$ 5,100.0
Accrued expenses		47.2	47.2
Cancellable future commitments		669.0	669.0
Liabilities associated with uncertain tax positions		172.0	172.0
Income taxes paid			185.4
2017 Tax Act
Business Acquisition [Line Items]
Transition toll tax liabilities		419.5	419.5	$ 558.0
Development Milestones
Business Acquisition [Line Items]
Potential future milestone payments commitment, approximately		900.0	900.0
Regulatory Milestones
Business Acquisition [Line Items]
Potential future milestone payments commitment, approximately		400.0	400.0
Commercial Milestones
Business Acquisition [Line Items]
Potential future milestone payments commitment, approximately		3,800.0	$ 3,800.0
Maximum \| ADUHELM
Business Acquisition [Line Items]
Research and development expense asset acquired				$ 335.0
Ionis Pharmaceuticals
Business Acquisition [Line Items]
Research and development expense asset acquired	$ 45.0
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					$ 109.0
Eisai \| ADUHELM \| Regulatory Milestones \| Neurimmune
Business Acquisition [Line Items]
Potential future milestone payments commitment, approximately						$ 100.0
Sage Therapeutics
Business Acquisition [Line Items]
Research and development expense asset acquired		$ 75.0
TYSABRI
Business Acquisition [Line Items]
Future contingent payment for annual worldwide net sales up to threshold, percentage		18.00%	18.00%
Future contingent payment threshold		$ 2,000.0	$ 2,000.0
Future contingent payment for annual worldwide net sales that exceeding threshold, percentage		25.00%	25.00%