SCOPE OF CONSOLIDATION - Investment in Associates and Joint Arrangements (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Basis Of Consolidation [Abstract]
Joint ventures	$ 3,006,000,000	$ 2,586,000,000
Associates	2,847,000,000	2,859,000,000
Individually immaterial joint ventures and associates	964,000,000	1,084,000,000
Total	$ 6,817,000,000	$ 6,529,000,000
Threshold aggregate of individually immaterial joint ventures and associates (in percent)	20.00%	20.00%
Threshold carrying amount of individually immaterial joint ventures and associates	$ 100,000,000	$ 100,000,000

The amount of investments accounted for using the equity method. The equity method is a method of accounting whereby the investment is initially recognised at cost and adjusted thereafter for the post-acquisition change in the investor's share of net assets of the investee. The investor's profit or loss includes its share of the profit or loss of the investee. The investor's other comprehensive income includes its share of the other comprehensive income of the investee. [Refer: At cost [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 8
-IssueDate 2020-01-01
-Paragraph 24
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2020-en-r&anchor=para_24_a&doctype=Standard
-URIDate 2020-01-01

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 12
-IssueDate 2020-01-01
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-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2020-en-r&anchor=para_B16&doctype=Appendix&subtype=B
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
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-IssueDate 2020-01-01
-Paragraph 54
-Subparagraph e
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The amount of investments in associates accounted for using the equity method. [Refer: Associates [member]; Investments accounted for using equity method]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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The amount of investments in joint ventures accounted for using the equity method. [Refer: Joint ventures [member]; Investments accounted for using equity method]

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Basis Of Consolidation [Abstract]

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Threshold Aggregate Of Individually Immaterial Joint Ventures And Associates

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