INCOME TAXES - Components of tax PL (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current taxes
Attributed to the current period	$ (65)	$ (30)	$ (39)
Deferred taxes
Income taxes - origination and reversal of temporary differences	26	2	8
Relating to change in tax rates / imposition of new tax laws	1	95	(42)
Relating to unrecognized temporary differences and tax losses	(13)	(8)	(15)
Deferred taxes, net	14	89	(49)
Total income tax recovery (expense)	$ (51)	$ 59	$ (88)

The amount of income taxes payable (recoverable) in respect of the taxable profit (tax loss) for a period.

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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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The amount of deferred tax expense or income relating to the creation or reversal of temporary differences. [Refer: Temporary differences [member]; Deferred tax expense (income)]

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The amount of deferred tax expense or income relating to tax rate changes or the imposition of new taxes. [Refer: Deferred tax expense (income)]

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The aggregate amount included in the determination of profit (loss) for the period in respect of current tax and deferred tax. [Refer: Current tax expense (income); Deferred tax expense (income)]

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The amount of benefit arising from a previously unrecognised tax loss, tax credit or temporary difference of a prior period that is used to reduce deferred tax expense. [Refer: Deferred tax expense (income); Temporary differences [member]; Unused tax losses [member]; Unused tax credits [member]]

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