FINANCIAL RISK MANAGEMENT - Maximum Exposure Credit Risk (Details) - Credit risk - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Disclosure of detailed information about financial instruments [line items]
Maximum exposure to credit risk	$ 5,746	$ 3,677
Cash and equivalents
Disclosure of detailed information about financial instruments [line items]
Maximum exposure to credit risk	5,188	3,314
Accounts receivable
Disclosure of detailed information about financial instruments [line items]
Maximum exposure to credit risk	$ 558	$ 363

The amount that best represents the maximum exposure to credit risk without taking into account any collateral held or other credit enhancements (for example, netting agreements that do not qualify for offset in accordance with IAS 32). [Refer: Credit risk [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2019-01-01
-Paragraph 35K
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2019-en-r&anchor=para_35K_a&doctype=Standard
-URIDate 2019-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2021-01-01
-Name IFRS
-Number 7
-IssueDate 2019-01-01
-Paragraph 36
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2017-en-b&anchor=para_36_a&doctype=Standard&book=b
-URIDate 2019-03-27

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