Derivatives and Risk Management (Balance Sheet Classification of Derivative Financial Instruments) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Derivatives, Fair Value [Line Items]
Net current derivative liabilities	$ (1,098)	$ (4)
Net long-term derivative liabilities	(407)	(38)
Non-performance risk adjustment	3	1
Total	(1,502)	(41)
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative assets	411	387
Derivative liabilities	1,916	429
Not Designated as Hedging Instrument \| Interest rate swaps \| Other long-term assets
Derivatives, Fair Value [Line Items]
Derivative assets	2	0
Natural gas storage \| Not Designated as Hedging Instrument \| Fixed price swaps \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	1	0
Natural Gas \| Not Designated as Hedging Instrument \| Purchased fixed price swaps \| Derivative assets \| Purchased
Derivatives, Fair Value [Line Items]
Derivative assets	0	1
Natural Gas \| Not Designated as Hedging Instrument \| Fixed price swaps \| Derivative assets
Derivatives, Fair Value [Line Items]
Derivative assets	79	37
Natural Gas \| Not Designated as Hedging Instrument \| Fixed price swaps \| Other long-term assets
Derivatives, Fair Value [Line Items]
Derivative assets	64	7
Natural Gas \| Not Designated as Hedging Instrument \| Fixed price swaps \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	565	7
Natural Gas \| Not Designated as Hedging Instrument \| Fixed price swaps \| Other long-term liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	246	3
Natural Gas \| Not Designated as Hedging Instrument \| Two-way costless collars \| Derivative assets
Derivatives, Fair Value [Line Items]
Derivative assets	9	54
Natural Gas \| Not Designated as Hedging Instrument \| Two-way costless collars \| Other long-term assets
Derivatives, Fair Value [Line Items]
Derivative assets	100	20
Natural Gas \| Not Designated as Hedging Instrument \| Two-way costless collars \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	104	43
Natural Gas \| Not Designated as Hedging Instrument \| Two-way costless collars \| Other long-term liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	115	21
Natural Gas \| Not Designated as Hedging Instrument \| Three-way costless collars \| Derivative assets
Derivatives, Fair Value [Line Items]
Derivative assets	12	57
Natural Gas \| Not Designated as Hedging Instrument \| Three-way costless collars \| Other long-term assets
Derivatives, Fair Value [Line Items]
Derivative assets	37	87
Natural Gas \| Not Designated as Hedging Instrument \| Three-way costless collars \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	298	82
Natural Gas \| Not Designated as Hedging Instrument \| Three-way costless collars \| Other long-term liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	178	103
Natural Gas \| Not Designated as Hedging Instrument \| Basis swaps \| Derivative assets
Derivatives, Fair Value [Line Items]
Derivative assets	77	60
Natural Gas \| Not Designated as Hedging Instrument \| Basis swaps \| Other long-term assets
Derivatives, Fair Value [Line Items]
Derivative assets	22	15
Natural Gas \| Not Designated as Hedging Instrument \| Basis swaps \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	9	3
Natural Gas \| Not Designated as Hedging Instrument \| Basis swaps \| Other long-term liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	22	7
Natural Gas \| Not Designated as Hedging Instrument \| Call options \| Derivative assets
Derivatives, Fair Value [Line Items]
Derivative assets	0	4
Natural Gas \| Not Designated as Hedging Instrument \| Call options \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	67	12
Natural Gas \| Not Designated as Hedging Instrument \| Call options \| Other long-term liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	42	28
Natural Gas \| Not Designated as Hedging Instrument \| Put options \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	0	1
Natural Gas \| Not Designated as Hedging Instrument \| Swaptions \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	0	2
Oil \| Not Designated as Hedging Instrument \| Fixed price swaps \| Derivative assets
Derivatives, Fair Value [Line Items]
Derivative assets	0	13
Oil \| Not Designated as Hedging Instrument \| Fixed price swaps \| Other long-term assets
Derivatives, Fair Value [Line Items]
Derivative assets	0	2
Oil \| Not Designated as Hedging Instrument \| Fixed price swaps \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	60	12
Oil \| Not Designated as Hedging Instrument \| Fixed price swaps \| Other long-term liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	9	2
Oil \| Not Designated as Hedging Instrument \| Two-way costless collars \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	0	1
Oil \| Not Designated as Hedging Instrument \| Two-way costless collars \| Other long-term liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	0	0
Oil \| Not Designated as Hedging Instrument \| Three-way costless collars \| Derivative assets
Derivatives, Fair Value [Line Items]
Derivative assets	1	15
Oil \| Not Designated as Hedging Instrument \| Three-way costless collars \| Other long-term assets
Derivatives, Fair Value [Line Items]
Derivative assets	3	15
Oil \| Not Designated as Hedging Instrument \| Three-way costless collars \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	24	15
Oil \| Not Designated as Hedging Instrument \| Three-way costless collars \| Other long-term liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	21	15
Ethane \| Not Designated as Hedging Instrument \| Fixed price swaps \| Derivative assets
Derivatives, Fair Value [Line Items]
Derivative assets	2	0
Ethane \| Not Designated as Hedging Instrument \| Fixed price swaps \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	10	10
Ethane \| Not Designated as Hedging Instrument \| Two-way costless collars \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	1	0
Propane \| Not Designated as Hedging Instrument \| Fixed price swaps \| Derivative assets
Derivatives, Fair Value [Line Items]
Derivative assets	2	0
Propane \| Not Designated as Hedging Instrument \| Fixed price swaps \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	78	36
Propane \| Not Designated as Hedging Instrument \| Fixed price swaps \| Other long-term liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	1	2
Propane \| Not Designated as Hedging Instrument \| Three-way costless collars \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	4	0
Normal Butane \| Not Designated as Hedging Instrument \| Fixed price swaps \| Derivative assets
Derivatives, Fair Value [Line Items]
Derivative assets	1	0
Normal Butane \| Not Designated as Hedging Instrument \| Fixed price swaps \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	27	8
Normal Butane \| Not Designated as Hedging Instrument \| Fixed price swaps \| Other long-term liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	0	1
Natural Gasoline \| Not Designated as Hedging Instrument \| Fixed price swaps \| Derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	33	13
Natural Gasoline \| Not Designated as Hedging Instrument \| Fixed price swaps \| Other long-term liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	$ 1	$ 2

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

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- Definition

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

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Derivative Assets (Liabilities), Non-Performance Risk Adjustment

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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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