Derivative instruments (Effective Portion of Unrealized Gain (Loss)) (Details) - Cash flow hedge [Member] - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Derivative Instruments, Gain (Loss) [Line Items]
Total unrealized gains (losses)	$ 56	$ 108
Foreign currency contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total unrealized gains (losses)	78	183
Cross-currency swap contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total unrealized gains (losses)	$ (22)	$ (75)

Amount, before tax and after reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=124509347&loc=SL7669646-108580

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=124509347&loc=d3e637-108580

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Period Type:	duration