SEGMENTED INFORMATION - Reconciliation of FFO to Equity Accounted Investments (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Disclosure of operating segments [abstract]
Consolidated equity accounted income	$ 1,003	$ 342	$ 1,347	$ 630
Non-FFO items from equity accounted investments	(379)	(283)	128	(616)
FFO from equity accounted investments	$ 624	$ 625	$ 1,219	$ 1,246

The entity's share of the profit (loss) of associates and joint ventures accounted for using the equity method. [Refer: Associates [member]; Investments accounted for using equity method; Joint ventures [member]; Profit (loss)]

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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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