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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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Acquisitions and divestitures - Five Prime Therapeutics Inc. (Details) - USD ($) $ in Millions		12 Months Ended
	Apr. 16, 2021	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Business Acquisition [Line Items]
Total cash consideration		$ 26,989	$ 3,839	$ 2,529
Acquired in-process research and development		$ 0	$ 0	$ 1,505
Five Prime Therapeutics, Inc.
Business Acquisition [Line Items]
Total cash consideration	$ 1,600
Acquired in-process research and development	1,500
Deferred tax asset	177
Other liabilities	$ 47