Income Taxes (Unaudited) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Income Tax Disclosure [Abstract]
Consolidated effective income tax rate (percent)			(302.00%)	38.00%
Schedule Of Income Taxes [Line Items]
U.S. operations			$ 73	$ 2
International operations			(254)	(1,545)
Total	$ (91)	$ (522)	(181)	$ (1,543)
Historical deferred tax adjustments			(49)
Settlement of state income tax examination	$ (24)		$ (24)

Adjustment to Historical Tax Positions

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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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The amount of the additional liability or refund received or expected based on a final settlement with a taxing authority.

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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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