Incentive Compensation / 401(k) Retirement Plan - Overview Narrative (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized number of awards to grant (in shares)	36,832,525
Shares remaining for issuance (in shares)	10,579,000
Compensation expense recorded	$ 9	$ 14
Income tax benefit	$ 0	0
Class B Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional shares of common stock available for issuance (in shares)	0
EP Energy Corporation
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Income tax benefit	$ 2	$ 4

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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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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