Accounting for Derivative Instruments and Hedging Activities - Pre-tax Effects of Economic Hedges not Designated as Cash Flow Hedges (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Unrealized Mark To Market Results [Abstract]
Reversal of previously recognized unrealized (gains) on settled positions related to economic hedges	$ (1,232)	$ (41)	$ (55)
Reversal of acquired loss positions related to economic hedges	2	256	4
Total unrealized mark-to-market gains/(losses) for economic hedging activities	1,248	2,716	(119)
Reversal of previously recognized unrealized losses/(gains) on settled positions related to trading activity	13	(18)	(20)
Reversal of Acquired (gain) Positions Related to Trading Activity	0	(1)	0
Net unrealized (losses)/gains on open positions related to trading activity	(17)	(13)	15
Total unrealized mark-to-market (losses) for trading activity	(4)	(32)	(5)
Total unrealized gains/(losses)	1,244	2,684	(124)
Credit Risk Related Contingent Features [Abstract]
Collateral required contracts with credit rating contingent features in a net liability position	195
Additional collateral required	30
Adequate Assurance Clauses
Credit Risk Related Contingent Features [Abstract]
Collateral required for contracts in net liability positions that have adequate assurance clauses	1,500
Not Designated as Hedging Instrument, Economic Hedge
Unrealized Mark To Market Results [Abstract]
Net unrealized gains/(losses) on open positions related to economic hedges	2,478	2,501	(68)
Commodity contracts
Unrealized Mark To Market Results [Abstract]
Total unrealized gains/(losses)	1,244	2,684	(124)
Commodity contracts \| Operating revenue
Unrealized Mark To Market Results [Abstract]
Total unrealized gains/(losses)	(87)	(196)	90
Commodity contracts \| Cost of operations
Unrealized Mark To Market Results [Abstract]
Total unrealized gains/(losses)	1,315	2,880	(214)
Foreign exchange contract \| Cost of operations
Unrealized Mark To Market Results [Abstract]
Total unrealized gains/(losses)	$ 16	$ 0	$ 0

-- None. No documentation exists for this element. --

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- Definition

This element represents the amount recorded in the entity's statement of operations for net unrealized gains (losses) on open positions related to trading activities.

+ References

No definition available.

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Reversal of Acquired (gain) Positions Related to Trading Activity

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Amount reversed into entity's statement of operations for previously recognized unrealized (gains) losses on settled positions related to acquired economic hedges.

+ References

No definition available.

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Amount reversed into entity's statement of operations for previously recognized unrealized (gains) losses on settled positions related to economic hedges.

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No definition available.

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Amount reversed into entity's statement of operations for previously recognized unrealized (gains) losses on settled positions related to trading activities.

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No definition available.

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- Definition

Unrealized Gain (Loss) on Derivatives, Mark To Market, Economic Hedging Activities

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No definition available.

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Unrealized Gain (Loss) on Derivatives, Mark To Market, Trading Activities

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- Definition

The aggregate fair value of additional assets that would be required to be posted as collateral for derivative instruments with credit-risk-related contingent features if the credit-risk-related contingent features were triggered at the end of the reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (e)
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The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (d)
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The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5624258-113959

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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of open derivatives, commodity, or energy contracts, held at each balance sheet date, that was included in earnings for the period.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of open agreements to purchase or sell energy at some future point, held at each balance sheet date, that was included in earnings for the period.

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