Collaborative Arrangements - Daiicho Sankyo (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2023	Dec. 31, 2024
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Selling, general and administrative	$ 2,552	$ 2,483
Research and development	3,621	3,992
Other current assets	9,289			$ 8,706
Accrued and other current liabilities	12,772			15,694
Daiichi Sankyo \| Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Selling, general and administrative	9	3
Research and development	128	$ 69	$ 5,500
Other current assets	13			8
Accrued and other current liabilities	$ 803			$ 817

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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