Derivative instruments (Details Textual) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Foreign currency and cross currency swap contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amounts expected to be reclassified from AOCI into earnings over the next 12 months, foreign currency and cross-currency swaps	$ 97
Derivatives designated as hedging instrument [Member] \| Foreign currency forward contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional amounts	4,600	$ 4,500
Derivatives designated as hedging instrument [Member] \| Foreign currency option contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional amounts		21
Derivatives designated as hedging instrument [Member] \| Interest rate swap [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional amounts	9,550	10,950
Derivatives not designated as hedging instrument [Member] \| Foreign currency forward contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional amounts	$ 857	$ 737
Notes [Member] \| 2.125% €675 million notes due 2019 (2.125% 2019 euro Notes) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Interest rate, stated percentage	2.125%

Contractual interest rate for funds borrowed, under the debt agreement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

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- Definition

The estimated net amount of unrealized gains or losses on foreign currency cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=112277219&loc=d3e80748-113994

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