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Collaborative Arrangement, Rights and Obligations, Probable Contingent Payments

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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 after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of liability recognized for present obligation requiring transfer or otherwise providing economic benefit to others.

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Collaborative Arrangements - Eisai Co., Ltd. - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Amortization expense for intangible assets	$ 2,800	$ 2,400	$ 2,000
Licenses and other
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Intangible assets	3,203	3,091
Alliance revenue - Lenvima \| Licenses and other
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Intangible assets	201
Eisai \| Alliance revenue - Lenvima
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Amortization expense for intangible assets			154
Eisai \| Alliance revenue - Lenvima \| Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Probable contingent payments			250
Liabilities			250
Milestone payments sales-based		$ 125	$ 125
Sales milestone payments	$ 2,300