Derivatives - Schedule of Derivative Instruments in the Consolidated Balance Sheets (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Derivatives, Fair Value [Line Items]
Asset	$ 69	$ 12
Liability	38	6
Net Asset (Liability)	31	6
Not Designated as Hedges
Derivatives, Fair Value [Line Items]
Asset	60	10
Liability	19	6
Net Asset (Liability)	41	4
Cash Flow Hedges
Derivatives, Fair Value [Line Items]
Asset	9	2
Liability	19	0
Net Asset (Liability)	(10)	2
Commodity \| Other current assets \| Not Designated as Hedges
Derivatives, Fair Value [Line Items]
Asset	59	9
Liability	14	1
Net Asset (Liability)	45	8
Commodity \| Deferred credits and other liabilities \| Not Designated as Hedges
Derivatives, Fair Value [Line Items]
Asset	0
Liability	2
Net Asset (Liability)	(2)
Commodity \| Other noncurrent assets \| Not Designated as Hedges
Derivatives, Fair Value [Line Items]
Asset		1
Liability		0
Net Asset (Liability)		1
Commodity \| Other current liabilities \| Not Designated as Hedges
Derivatives, Fair Value [Line Items]
Asset		0
Liability		5
Net Asset (Liability)		(5)
Interest Rate \| Deferred credits and other liabilities \| Not Designated as Hedges
Derivatives, Fair Value [Line Items]
Asset	0
Liability	3
Net Asset (Liability)	(3)
Interest Rate \| Deferred credits and other liabilities \| Cash Flow Hedges
Derivatives, Fair Value [Line Items]
Asset	0
Liability	19
Net Asset (Liability)	(19)
Interest Rate \| Other noncurrent assets \| Not Designated as Hedges
Derivatives, Fair Value [Line Items]
Asset	1
Liability	0
Net Asset (Liability)	1
Interest Rate \| Other noncurrent assets \| Cash Flow Hedges
Derivatives, Fair Value [Line Items]
Asset	9	2
Liability	0	0
Net Asset (Liability)	$ 9	$ 2

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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- Definition

Fair value of the assets less the liabilities of a derivative or group of derivatives.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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