Derivatives and Risk Management (Balance Sheet Classification of Derivative Financial Instruments) (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Derivatives, Fair Value [Line Items]
Net current derivative asset (liability)	$ 54	$ (1,174)
Net long-term derivative liabilities	(7)	(307)
Non-performance risk adjustment	(1)	3
Derivative instruments, net	46	(1,478)
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative assets	667	218
Derivative liabilities	620	1,699
Natural Gas \| Not Designated as Hedging Instrument \| Fixed price swaps \| Derivative assets
Derivatives, Fair Value [Line Items]
Derivative assets	227	0
Natural Gas \| Not Designated as Hedging Instrument \| Fixed price swaps \| Other long-term assets
Derivatives, Fair Value [Line Items]
Derivative assets	105	28
Natural Gas \| Not Designated as Hedging Instrument \| Fixed price swaps \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	97	581
Natural Gas \| Not Designated as Hedging Instrument \| Fixed price swaps \| Long-term derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	108	281
Natural Gas \| Not Designated as Hedging Instrument \| Two-way costless collars \| Derivative assets
Derivatives, Fair Value [Line Items]
Derivative assets	137	47
Natural Gas \| Not Designated as Hedging Instrument \| Two-way costless collars \| Other long-term assets
Derivatives, Fair Value [Line Items]
Derivative assets	16	18
Natural Gas \| Not Designated as Hedging Instrument \| Two-way costless collars \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	112	235
Natural Gas \| Not Designated as Hedging Instrument \| Two-way costless collars \| Long-term derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	26	56
Natural Gas \| Not Designated as Hedging Instrument \| Three-way costless collars \| Derivative assets
Derivatives, Fair Value [Line Items]
Derivative assets	51	18
Natural Gas \| Not Designated as Hedging Instrument \| Three-way costless collars \| Other long-term assets
Derivatives, Fair Value [Line Items]
Derivative assets	66	3
Natural Gas \| Not Designated as Hedging Instrument \| Three-way costless collars \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	91	311
Natural Gas \| Not Designated as Hedging Instrument \| Three-way costless collars \| Long-term derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	73	20
Natural Gas \| Not Designated as Hedging Instrument \| Basis swaps \| Derivative assets
Derivatives, Fair Value [Line Items]
Derivative assets	15	64
Natural Gas \| Not Designated as Hedging Instrument \| Basis swaps \| Other long-term assets
Derivatives, Fair Value [Line Items]
Derivative assets	9	17
Natural Gas \| Not Designated as Hedging Instrument \| Basis swaps \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	41	69
Natural Gas \| Not Designated as Hedging Instrument \| Basis swaps \| Long-term derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	2	1
Natural Gas \| Not Designated as Hedging Instrument \| Put options \| Derivative assets
Derivatives, Fair Value [Line Items]
Derivative assets	6	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	6	0
Natural Gas \| Not Designated as Hedging Instrument \| Call options \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	27	70
Natural Gas \| Not Designated as Hedging Instrument \| Call options \| Long-term derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	0	18
Oil \| Not Designated as Hedging Instrument \| Fixed price swaps \| Derivative assets
Derivatives, Fair Value [Line Items]
Derivative assets	1	0
Oil \| Not Designated as Hedging Instrument \| Fixed price swaps \| Other long-term assets
Derivatives, Fair Value [Line Items]
Derivative assets	2	1
Oil \| Not Designated as Hedging Instrument \| Fixed price swaps \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	14	20
Oil \| Not Designated as Hedging Instrument \| Fixed price swaps \| Long-term derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	0	4
Oil \| Not Designated as Hedging Instrument \| Two-way costless collars \| Derivative assets
Derivatives, Fair Value [Line Items]
Derivative assets	2	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	2	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	18	31
Ethane \| Not Designated as Hedging Instrument \| Fixed price swaps \| Derivative assets
Derivatives, Fair Value [Line Items]
Derivative assets	12	4
Ethane \| Not Designated as Hedging Instrument \| Fixed price swaps \| Other long-term assets
Derivatives, Fair Value [Line Items]
Derivative assets	1	1
Ethane \| Not Designated as Hedging Instrument \| Fixed price swaps \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	0	1
Propane \| Not Designated as Hedging Instrument \| Fixed price swaps \| Derivative assets
Derivatives, Fair Value [Line Items]
Derivative assets	11	9
Propane \| Not Designated as Hedging Instrument \| Fixed price swaps \| Other long-term assets
Derivatives, Fair Value [Line Items]
Derivative assets	1	1
Propane \| Not Designated as Hedging Instrument \| Fixed price swaps \| 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	1	1
Normal Butane \| Not Designated as Hedging Instrument \| Fixed price swaps \| Other long-term assets
Derivatives, Fair Value [Line Items]
Derivative assets	1	0
Natural Gasoline \| Not Designated as Hedging Instrument \| Fixed price swaps \| Derivative assets
Derivatives, Fair Value [Line Items]
Derivative assets	1	1
Natural Gasoline \| Not Designated as Hedging Instrument \| Fixed price swaps \| Other long-term assets
Derivatives, Fair Value [Line Items]
Derivative assets	1	0
Natural Gasoline \| Not Designated as Hedging Instrument \| Fixed price swaps \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	$ 1	$ 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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Derivative Assets (Liabilities), Non-Performance Risk Adjustment

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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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