Acquisitions and divestitures - Summary of Pro Forma Revenue for Horizon Therapeutics (Details) - Horizon Therapeutics - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Business Acquisition [Line Items]
Total revenue	$ 30,969	$ 29,964
Net income	$ 5,383	$ 2,381

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479328/805-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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