RELATED PARTY TRANSACTIONS RELATED PARTY TRANSACTIONS - Related Party Balances included within Consolidated Financial Statements (Details) - Other related parties [member] - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Disclosure of transactions between related parties [line items]
Management fees received	$ 31	$ 97
Management fees received	$ 31	$ 97

The amount of revenue arising from the rendering of services in related party transactions. [Refer: Revenue; Related parties [member]]

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Name IAS
-Number 24
-IssueDate 2019-01-01
-Paragraph 21
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=24&code=ifrs-tx-2019-en-r&anchor=para_21_c&doctype=Standard
-URIDate 2019-03-27

Name:	ifrs-full_RevenueFromRenderingOfServicesRelatedPartyTransactions
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration