Collaborative Arrangements - Eisai Co., Ltd. - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Amortization expense for intangible assets	$ 2,400	$ 2,000	$ 2,100
Licenses and other
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Intangible assets	3,091	3,212
Alliance revenue - Lenvima | Licenses and other
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Intangible assets	442
Eisai
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]
Milestone payments sales-based	125	125	600
Probable contingent payments		250
Liabilities		$ 250
Sales milestone payments	$ 2,300
Regulatory milestone payments			50
Bayer AG | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestone payments sales-based			$ 400