Collaborative Arrangements - Daiicho Sankyo (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2023	Dec. 31, 2024
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Selling, general and administrative	$ 2,649	$ 2,739	$ 5,202	$ 5,221
Research and development	4,048	3,500	7,669	7,492
Other current assets	9,996		9,996			$ 8,706
Accrued and other current liabilities	14,502		14,502			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	4	14	13	16
Research and development	193	$ 65	321	$ 133	$ 5,500
Other current assets	21		21			8
Accrued and other current liabilities	$ 850		$ 850			$ 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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