Goodwill and other intangible assets - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization charges associated with finite-lived intangible assets	$ 2,600	$ 2,800	$ 1,400
Total estimated amortization of finite-lived intangible assets for 2022	2,500
Total estimated amortization of finite-lived intangible assets for 2023	2,500
Total estimated amortization of finite-lived intangible assets for 2024	2,400
Total estimated amortization of finite-lived intangible assets for 2025	2,200
Total estimated amortization of finite-lived intangible assets for 2026	1,800
Teneobio, Inc. | IPR&D
Finite-Lived Intangible Assets [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill	1,100
Teneobio, Inc. | Developed Technology Rights
Finite-Lived Intangible Assets [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill	94
Teneobio, Inc. | Favorable Contract
Finite-Lived Intangible Assets [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill	$ 41