Consolidated Statement of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Condensed Statement of Income Captions [Line Items]
Cumulative translation adjustments, net	$ (6,409)	$ (814)	$ 10,986
Associates and joint ventures [member]
Condensed Statement of Income Captions [Line Items]
Cumulative translation adjustments, net	$ 236	$ 49	$ 413

The amount of other comprehensive income, net of tax, related to exchange differences when financial statements of foreign operations are translated. [Refer: Other comprehensive income]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2018-01-01
-Paragraph 91
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_91_a&doctype=Standard
-URIDate 2018-03-16

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2018-01-01
-Paragraph 7
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_7&doctype=Standard
-URIDate 2018-03-16

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