Acquisitions and divestitures - Aggregate Consideration Paid (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2022	Dec. 31, 2021
Business Acquisition [Line Items]
Goodwill	$ 14,845	$ 14,890
Teneobio
Business Acquisition [Line Items]
Cash purchase price	993
Contingent consideration	299
Total consideration	1,292
Cash and cash equivalents	100
In-process research and development	991
Goodwill	273
Other assets, net	16
Deferred tax liability	(244)
Total assets acquired, net	1,292
Teneobio | R & D Technology rights
Business Acquisition [Line Items]
Finite-lived intangible assets	115
Teneobio | Licensing rights
Business Acquisition [Line Items]
Finite-lived intangible assets	$ 41