INCOME TAXES - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Income taxes provision (benefit)	$ (18)	$ 51	$ (101)	$ 74
Tax expense (benefit) for discrete items			(46)	203
Tax benefit, royalty payments by affiliate			32
Income tax benefit related to filing certain tax returns			13
Tax charges related to changes in uncertain tax positions			1
Income tax benefit on ordinary income			55	129
Income tax charge for internal restructuring transactions				255
Income tax benefit related to impairment of intangible assets				$ 57
Valuation allowance against deferred tax assets	3,126		3,126		$ 2,913
Unrecognized tax benefits including interest and penalties	622		622		654
Unrecognized tax benefits related to interest and penalties	48		48		$ 42
Portion of unrecognized tax benefits, if recognized, would reduce the Company's effective tax rate	$ 316		$ 316

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

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Effective Income Tax Rate Reconciliation, Deductible Royalty Expense (Benefit), 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 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 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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