Income Taxes (Unaudited) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Income Tax Disclosure [Abstract]
Consolidated effective income tax rate (percent)			101.00%	35.00%
Schedule Of Income Taxes [Line Items]
U.S. operations			$ 20	$ 8
International operations			(110)	(1,029)
Total	$ 15	$ (515)	(90)	$ (1,021)
State law changes			18
Settlement of state income tax examination	$ 5		$ 5

Schedule Of Income Taxes [Line Items]

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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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Amount of current and deferred federal income tax expense (benefit) attributable to income (loss) from continuing operations.

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Amount of current and deferred foreign income tax expense (benefit) attributable to income (loss) from 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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Amount of income tax expense (benefit) from continuing operations attributable to an adjustment of a deferred tax liability or asset for enacted changes in tax laws or rates or a change in the tax status of the entity.

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