Fair value measurement (Details Textual) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Business Acquisition [Line Items]
Length of time hedged in foreign currency contracts (or less)	3 years
Long-term debt, fair value	$ 35,800	$ 33,700
Carrying value of debt	$ 31,848	$ 29,903
Other Government-related and Corporate Debt Securities [Member]
Business Acquisition [Line Items]
Investment maturity period	3 years

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- Definition

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, 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

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.

+ References

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-Publisher FASB
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- Definition

Fair value portion of notes payable.

+ References

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