INCOME TAXES - Deferred Income Tax Movement (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Reconciliation of changes in deferred tax liability (asset) [abstract]
Opening net deferred tax (liability)/asset	$ (587)	$ (663)
Recognized in income	132	88
Recognized in other comprehensive income	15	(2)	$ 0
Recognized in other	(696)	(10)
Net deferred tax (liability)/asset	$ (1,136)	$ (587)	$ (663)

The amount of tax expense or income relating to changes in deferred tax liabilities and deferred tax assets, recognised in profit or loss. [Refer: Deferred tax assets; Deferred tax expense (income); Deferred tax liabilities]

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- Definition

The amount of deferred tax liabilities or assets. [Refer: Deferred tax liabilities; Deferred tax assets]

+ References

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The amount of deferred tax related to items credited (charged) directly to equity. [Refer: Deferred tax expense (income)]

+ References

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

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

+ References

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No definition available.

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