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Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Maximum period of time the entity is hedging its exposure to variability in future cash flows for forecasted transactions, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Excludes forecasted transactions related to payment of variable interest on existing financial instruments.

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Fair value portion of notes payable.

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Fair value measurement - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2018	Jan. 02, 2020	Dec. 31, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Length of time hedged in foreign currency contracts	3 years
Aggregate fair value of long-term debt, including current portion	$ 39,400			$ 33,700
Carrying value of long-term debt, including current portion	32,986			$ 29,903
Other operating income (expense) [Member] \| IPR&D [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
IPR&D impairment charge		$ 330
BeiGene
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity Method Investment, Quoted Market Value	4,900		$ 2,600
Approximate carrying value of the company's equity method investment	$ 2,900