GOODWILL - Schedule of Changes in Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Reconciliation of changes in goodwill [abstract]
Beginning balance	$ 8,815	$ 5,317
Acquisitions through business combinations	6,125	4,158
Impairment losses	(453)	0
Foreign currency translation and other	63	(660)
Ending balance	14,550	8,815
Costs
Reconciliation of changes in goodwill [abstract]
Beginning balance	9,198	5,707
Acquisitions through business combinations	6,125	4,158
Impairment losses	0	0
Foreign currency translation and other	89	(667)
Ending balance	15,412	9,198
Accumulated Impairment
Reconciliation of changes in goodwill [abstract]
Beginning balance	(383)	(390)
Acquisitions through business combinations	0	0
Impairment losses	(453)	0
Foreign currency translation and other	(26)	7
Ending balance	$ (862)	$ (383)

Acquisitions through business combinations, goodwill

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- Definition

The amount of assets representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognised. [Refer: Business combinations [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The amount of impairment loss recognised in profit or loss for goodwill. [Refer: Impairment loss recognised in profit or loss; Goodwill]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
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- Definition

The increase (decrease) in goodwill resulting from net exchange differences arising on the translation of the financial statements from the functional currency into a different presentation currency, including the translation of a foreign operation into the presentation currency of the reporting entity. [Refer: Goodwill]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References

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