Derivatives and Risk Management (Balance Sheet Classification of Derivative Financial Instruments) (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Derivatives, Fair Value [Line Items]
Net current derivative asset (liability)	$ 118	$ (1,174)
Net long-term derivative asset (liability)	(33)	(307)
Non-performance risk adjustment	(1)	3
Derivative instruments, net	84	(1,478)
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative assets	491	218
Derivative liabilities	406	1,699
Natural Gas \| Not Designated as Hedging Instrument \| Fixed price swaps \| Derivative assets
Derivatives, Fair Value [Line Items]
Derivative assets	224	0
Natural Gas \| Not Designated as Hedging Instrument \| Fixed price swaps \| Other long-term assets
Derivatives, Fair Value [Line Items]
Derivative assets	25	28
Natural Gas \| Not Designated as Hedging Instrument \| Fixed price swaps \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	73	581
Natural Gas \| Not Designated as Hedging Instrument \| Fixed price swaps \| Long-term derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	45	281
Natural Gas \| Not Designated as Hedging Instrument \| Two-way costless collars \| Derivative assets
Derivatives, Fair Value [Line Items]
Derivative assets	32	47
Natural Gas \| Not Designated as Hedging Instrument \| Two-way costless collars \| Other long-term assets
Derivatives, Fair Value [Line Items]
Derivative assets	43	18
Natural Gas \| Not Designated as Hedging Instrument \| Two-way costless collars \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	31	235
Natural Gas \| Not Designated as Hedging Instrument \| Two-way costless collars \| Long-term derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	37	56
Natural Gas \| Not Designated as Hedging Instrument \| Three-way costless collars \| Derivative assets
Derivatives, Fair Value [Line Items]
Derivative assets	28	18
Natural Gas \| Not Designated as Hedging Instrument \| Three-way costless collars \| Other long-term assets
Derivatives, Fair Value [Line Items]
Derivative assets	77	3
Natural Gas \| Not Designated as Hedging Instrument \| Three-way costless collars \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	39	311
Natural Gas \| Not Designated as Hedging Instrument \| Three-way costless collars \| Long-term derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	66	20
Natural Gas \| Not Designated as Hedging Instrument \| Basis swaps \| Derivative assets
Derivatives, Fair Value [Line Items]
Derivative assets	33	64
Natural Gas \| Not Designated as Hedging Instrument \| Basis swaps \| Other long-term assets
Derivatives, Fair Value [Line Items]
Derivative assets	8	17
Natural Gas \| Not Designated as Hedging Instrument \| Basis swaps \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	5	69
Natural Gas \| Not Designated as Hedging Instrument \| Basis swaps \| Long-term derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	0	1
Natural Gas \| Not Designated as Hedging Instrument \| Put options \| Derivative assets
Derivatives, Fair Value [Line Items]
Derivative assets	5	0
Natural Gas \| Not Designated as Hedging Instrument \| Put options \| Other long-term assets
Derivatives, Fair Value [Line Items]
Derivative assets	0	4
Natural Gas \| Not Designated as Hedging Instrument \| Put options \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	5	0
Natural Gas \| Not Designated as Hedging Instrument \| Call options \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	11	70
Natural Gas \| Not Designated as Hedging Instrument \| Call options \| Long-term derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	36	18
Oil \| Not Designated as Hedging Instrument \| Fixed price swaps \| Other long-term assets
Derivatives, Fair Value [Line Items]
Derivative assets	0	1
Oil \| Not Designated as Hedging Instrument \| Fixed price swaps \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	29	20
Oil \| Not Designated as Hedging Instrument \| Fixed price swaps \| Long-term derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	1	4
Oil \| Not Designated as Hedging Instrument \| Two-way costless collars \| Derivative assets
Derivatives, Fair Value [Line Items]
Derivative assets	1	0
Oil \| Not Designated as Hedging Instrument \| Two-way costless collars \| Other long-term assets
Derivatives, Fair Value [Line Items]
Derivative assets	1	0
Oil \| Not Designated as Hedging Instrument \| Two-way costless collars \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	4	0
Oil \| Not Designated as Hedging Instrument \| Two-way costless collars \| Long-term derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	1	0
Oil \| Not Designated as Hedging Instrument \| Three-way costless collars \| Derivative assets
Derivatives, Fair Value [Line Items]
Derivative assets	0	1
Oil \| Not Designated as Hedging Instrument \| Three-way costless collars \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	10	31
Ethane \| Not Designated as Hedging Instrument \| Fixed price swaps \| Derivative assets
Derivatives, Fair Value [Line Items]
Derivative assets	2	4
Ethane \| Not Designated as Hedging Instrument \| Fixed price swaps \| Other long-term assets
Derivatives, Fair Value [Line Items]
Derivative assets	0	1
Ethane \| Not Designated as Hedging Instrument \| Fixed price swaps \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	3	1
Propane \| Not Designated as Hedging Instrument \| Fixed price swaps \| Derivative assets
Derivatives, Fair Value [Line Items]
Derivative assets	10	9
Propane \| Not Designated as Hedging Instrument \| Fixed price swaps \| Other long-term assets
Derivatives, Fair Value [Line Items]
Derivative assets	0	1
Propane \| Not Designated as Hedging Instrument \| Fixed price swaps \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	7	0
Propane \| Not Designated as Hedging Instrument \| Fixed price swaps \| Long-term derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	1	0
Normal Butane \| Not Designated as Hedging Instrument \| Fixed price swaps \| Derivative assets
Derivatives, Fair Value [Line Items]
Derivative assets	2	1
Natural Gasoline \| Not Designated as Hedging Instrument \| Fixed price swaps \| Derivative assets
Derivatives, Fair Value [Line Items]
Derivative assets	0	1
Natural Gasoline \| Not Designated as Hedging Instrument \| Fixed price swaps \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	$ 2	$ 1

Derivative Assets (Liabilities), at Fair Value, Net, Current

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Derivative Assets (Liabilities), at Fair Value, Net, Noncurrent

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- Definition

Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

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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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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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