BORROWINGS - Additional Information (Details) - Non-recourse borrowings $ in Millions	6 Months Ended
Jun. 30, 2021 USD ($)
Disclosure of detailed information about borrowings [line items]
Decrease in borrowings	$ 263
U.K. regulated distribution business
Disclosure of detailed information about borrowings [line items]
Increase (decrease) through financing cash flows, liabilities arising from financing activities	$ 117

The increase (decrease) in liabilities arising from financing activities resulting from financing cash flows. [Refer: Cash flows from (used in) financing activities; Liabilities arising from financing activities]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 7
-IssueDate 2020-01-01
-Paragraph 44B
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=7&code=ifrs-tx-2020-en-r&anchor=para_44B_a&doctype=Standard
-URIDate 2020-01-01

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