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Collaborative Arrangements - Eisai Co., Ltd. (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Cost of sales	$ 3,855	$ 4,080	$ 10,831	$ 11,365
Selling, general and administrative	2,633	2,731	7,835	7,952
Research and development	4,234	5,862	11,903	13,354
Other current assets	47,557		47,557		$ 38,782
Eisai | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Revenue from collaborative arrangement	258	251	781	755
Cost of sales	60	60	181	181
Selling, general and administrative	33	40	99	120
Research and development	2	$ 4	10	$ 18
Other current assets	$ 258		$ 258		$ 257

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