INCOME TAXES - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Provision (benefit) from income taxes	$ 16	$ (26)
Provision (benefit) for discrete items	49	(21)
Provision related to withholding tax, intercompany dividends	46
Provision (benefit) related to filing certain tax returns	6	(4)
Tax benefit related to stock compensation	6	5
Provision (benefit) related to changes in uncertain tax positions	3	(10)
Income tax benefit on ordinary loss	33	$ 5
Valuation allowance against deferred tax assets	2,248		$ 2,252
Unrecognized tax benefits including interest and penalties	1,042		1,025
Unrecognized tax benefits related to interest and penalties	51		$ 49
Portion of unrecognized tax benefits, if recognized, would reduce the Company's effective tax rate	431
Unrecognized tax benefit, amount possible to decrease in next twelve months	$ 203

Effective Income Tax Rate Reconciliation, Discrete Items, Amount

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Effective Income Tax Rate Reconciliation, Expense Filing Tax Returns, Amount

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Effective Income Tax Rate Reconciliation, Withholding Tax, Intercompany Dividends, Amount

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The gross amount of unrecognized tax benefits including interest and penalties pertaining to uncertain tax positions taken in tax returns as of the balance sheet date.

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Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Amount of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to expense for award under share-based payment arrangement. Excludes expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in income tax contingencies. Including, but not limited to, domestic tax contingency, foreign tax contingency, state and local tax contingency, and other contingencies.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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