Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Segment Reporting Information [Line Items]
Income tax expense	$ 104	$ 148	$ 164	$ 320
Effective tax rate	(20.00%)	21.90%	(21.80%)	22.60%
Statutory federal rate	21.00%	21.00%	21.00%	21.00%
Goodwill impairment loss			$ 1,600
Natural Gas Pipelines Non-Regulated
Segment Reporting Information [Line Items]
Goodwill impairment loss	$ 1,000		$ 1,000

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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