Financial and other non-current assets - Other Non-current Assets (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Subclassifications of assets, liabilities and equities [abstract]
Deferred compensation plans	$ 137	$ 122
Prepaid post-employment benefit plans	24	13
Other non-current assets	50	50
Total other non-current assets	$ 211	$ 185

The amount of non-current assets that the entity does not separately disclose in the same statement or note. [Refer: Non-current assets]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2020-01-01
-Paragraph 55
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_55&doctype=Standard
-URIDate 2020-01-01

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant