Acquisitions and divestitures - Summary of Total Consideration for Teneobio Inc (Details) - USD ($) $ in Millions		12 Months Ended
	Dec. 31, 2022	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Business Acquisition [Line Items]
Contingent consideration		$ 0	$ 309	$ 0
Goodwill	$ 15,529	15,529	$ 14,890	$ 14,689
Teneobio
Business Acquisition [Line Items]
Cash purchase price	993
Contingent consideration	299
Total consideration	1,292
Cash and cash equivalents	100	100
Goodwill	273	273
Other assets, net	16	16
Deferred tax liability	(244)	(244)
Total assets acquired, net	1,292	1,292
Teneobio | R & D Technology rights
Business Acquisition [Line Items]
Finite-lived intangible assets	115	115
Teneobio | Licensing rights
Business Acquisition [Line Items]
Finite-lived intangible assets	41	41
Teneobio | IPR&D
Business Acquisition [Line Items]
IPR&D	$ 991	$ 991