Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Segment Reporting Information [Line Items]
Income tax expense	$ 60	$ 172
Effective tax rate	(26.00%)	23.30%
Statutory federal rate	21.00%	21.00%
CO2
Segment Reporting Information [Line Items]
Goodwill impairment loss	$ 600	$ 0

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

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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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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