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Unrecognized Tax Benefits, Potential Benefit

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Amount of deferred tax liability attributable to taxable temporary differences.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount of deferred tax liability attributable to taxable temporary differences from undistributed earnings of subsidiary and other recognized entity not within country of domicile. Includes, but is not limited to, other basis differences.

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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Carrying amount due within one year of the balance sheet date (or one operating cycle, if longer) from tax authorities as of the balance sheet date representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes.

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Carrying amount due after one year of the balance sheet date (or one operating cycle, if longer) from tax authorities as of the balance sheet date representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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The portion of the valuation allowance pertaining to the deferred tax asset representing potential future taxable deductions from net operating loss carryforwards for which it is more likely than not that a tax benefit will not be realized.

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The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Amount of unrecognized tax benefits.

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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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INCOME TAXES - NARRATIVE (Details) - USD ($)	12 Months Ended
INCOME TAXES - NARRATIVE (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Contingency [Line Items]
Worldwide effective tax rate	373.00%	26.00%	1.00%
Total deferred tax assets, after valuation allowances	$ 3,703,000,000	$ 1,343,000,000
Total deferred tax liabilities	13,364,000,000	2,250,000,000
Deferred foreign tax liability due to reversal of indefinite re-investment assertion	889,000,000
Additional deferred tax liability amount required	206,000,000
Unrecognized tax benefits	2,173,000,000	0	$ 22,000,000	$ 22,000,000
Potential benefit	2,000,000,000.0
Potential benefit, if recognized, would affect the effective tax rate on income	1,700,000,000
Benefits related to tax positions which ultimate deductibility is highly certain	131,000,000
Interest accrued related to liabilities for unrecognized tax benefits	199,000,000
Interest related to liabilities for unrecognized tax benefits	30,000,000
Interest and penalties associated with liabilities for unrecognized tax benefits		0	$ 0
Low end of range
Income Tax Contingency [Line Items]
Possible decrease to unrecognized tax benefit due to settlements with taxing authorities	100,000,000
High end of range
Income Tax Contingency [Line Items]
Possible decrease to unrecognized tax benefit due to settlements with taxing authorities	110,000,000
Other current assets
Income Tax Contingency [Line Items]
Income tax receivables	86,000,000	68,000,000
Long-term receivables and other assets, net
Income Tax Contingency [Line Items]
Federal alternative minimum tax non-current receivables	36,000,000	$ 68,000,000
Foreign
Income Tax Contingency [Line Items]
Tax credit carryforwards	4,400,000,000
Operating loss carryforwards	209,000,000
State
Income Tax Contingency [Line Items]
Tax credit carryforwards	39,000,000
Operating loss carryforwards	292,000,000
Operating loss carryforward, valuation allowance	240,000,000
Tax credit carryforward, valuation allowance	32,000,000
General business credits
Income Tax Contingency [Line Items]
Tax credit carryforwards	$ 404,000,000