Accrued expenses on funding commitment related to clinical research.

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- Definition

Future contingent payment for annual worldwide net sales that exceed $2.0 billion

+ References

No definition available.

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- Definition

Future contingent payment for annual worldwide net sales up to $2.0 billion

+ References

No definition available.

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- Definition

Future contingent payment threshold

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No definition available.

+ Details

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- Definition

Percentage of royalties as per collaboration.

+ References

No definition available.

+ Details

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- Definition

Potential future milestone payments commitment to third party approximately.

+ References

No definition available.

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- Definition

Royalties Payable Period, Post FDA Approval

+ References

No definition available.

+ Details

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- Definition

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

No definition available.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Section 50
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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Amount recognized for uncertainty in income taxes classified as current.

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- Definition

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.

+ References

No definition available.

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Commitments and Contingencies (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Oct. 31, 2019	Dec. 31, 2022	Dec. 31, 2016	Dec. 31, 2023	Dec. 31, 2021	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2013
Business Acquisition [Line Items]
Potential future milestone payments commitment, approximately		$ 9,300.0
Accrued expenses		20.4
Cancellable future commitments		929.0
Liabilities associated with uncertain tax positions		154.6
Income taxes paid		137.8
2017 Tax Act
Business Acquisition [Line Items]
Transition toll tax liabilities		558.0			$ 633.0
Development Milestones
Business Acquisition [Line Items]
Potential future milestone payments commitment, approximately		2,000.0
Regulatory Milestones
Business Acquisition [Line Items]
Potential future milestone payments commitment, approximately		500.0
Regulatory Milestones \| Neurimmune
Business Acquisition [Line Items]
Potential future milestone payments commitment, approximately							$ 75.0
Commercial Milestones
Business Acquisition [Line Items]
Potential future milestone payments commitment, approximately		$ 6,800.0
Ionis Pharmaceuticals \| Minimum \| SPINRAZA
Business Acquisition [Line Items]
Percentage of royalties as per collaboration		11.00%	11.00%
Ionis Pharmaceuticals \| Maximum \| SPINRAZA
Business Acquisition [Line Items]
Percentage of royalties as per collaboration		15.00%	15.00%
Alkermes \| VUMERITY
Business Acquisition [Line Items]
Percentage of royalties as per collaboration	15.00%	15.00%
Royalties payable period, post FDA approval	5 years
Aducanumab \| Forecast
Business Acquisition [Line Items]
Potential future milestone payments commitment, approximately				$ 356.2
Eisai \| ADUHELM \| Regulatory Milestones \| Neurimmune
Business Acquisition [Line Items]
Potential future milestone payments commitment, approximately						$ 100.0
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%