Fair value measurement - Narrative (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021	Jan. 02, 2020
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Aggregate fair value of long-term debt, including current portion	$ 35,000	$ 37,900
Carrying value of long-term debt, including current portion	38,945	33,309
BeiGene
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity Method Investment, Quoted Market Value	4,200	5,100	$ 2,600
Approximate carrying value of the company's equity method investment	2,200	$ 2,800
Teneobio, Inc.
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High	$ 1,600

For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

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- Definition

This item represents the aggregate value of each identified investment accounted for under the equity method of accounting based on the quoted market price for those investments in common stock for which a quoted market price is available.

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- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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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.

+ References

No definition available.

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- Definition

Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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- Definition

Fair value portion of notes payable.

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