INCOME TAXES - Schedule Of Components Of Income Taxes In Other Comprehensive Income (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Income Taxes [Abstract]
Revaluation of property, plant and equipment	$ 1,214	$ 623
Financial contracts and power sale agreements	(59)	6
Income tax relating to marketable securities measured at fair value through other comprehensive income	74	88
Foreign currency translation	37	(8)
Revaluation of pension obligation	(40)	(6)
Total deferred tax in other comprehensive income	$ 1,226	$ 703

Income Taxes [Abstract]

No definition available.

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- Definition

Income tax relating to marketable securities measured at fair value through other comprehensive income

+ References

No definition available.

+ Details

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- Definition

The amount of income tax relating to amounts recognised in other comprehensive income in relation to changes in a revaluation surplus. [Refer: Revaluation surplus; Other comprehensive income]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 12
-IssueDate 2019-01-01
-Paragraph 81
-Subparagraph ab
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=12&code=ifrs-tx-2019-en-r&anchor=para_81_ab&doctype=Standard
-URIDate 2019-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2019-01-01
-Paragraph 90
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_90&doctype=Standard
-URIDate 2019-03-27

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- Definition

The amount of income tax relating to amounts recognised in other comprehensive income. [Refer: Other comprehensive income]

+ References

+ Details

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- Definition

The amount of income tax relating to amounts recognised in other comprehensive income in relation to exchange differences on the translation of financial statements of foreign operations. [Refer: Other comprehensive income; Reserve of exchange differences on translation]

+ References

+ Details

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- Definition

The amount of income tax relating to amounts recognised in other comprehensive income in relation to financial assets measured at fair value through other comprehensive income. [Refer: Financial assets measured at fair value through other comprehensive income; Other comprehensive income]

+ References

+ Details

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- Definition

The amount of income tax relating to amounts recognised in other comprehensive income in relation to remeasurements of defined benefit plans. [Refer: Other comprehensive income; Reserve of remeasurements of defined benefit plans; Defined benefit plans [member]]

+ References

+ Details

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