BORROWINGS - Non-Recourse Borrowings (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Disclosure of detailed information about borrowings [line items]
Non-current Portion Of Non-current Non-recourse Borrowings	$ 3,114	$ 3,526
Non-recourse borrowings
Disclosure of detailed information about borrowings [line items]
Borrowings	$ 3,114	$ 3,526

The amount of outstanding funds that the entity is obligated to repay.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2019-01-01
-Paragraph 55
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_55&doctype=Standard
-URIDate 2019-03-27

Name:	ifrs-full_Borrowings
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant