Asset Retirement Obligations (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 27, 2022
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning balance as of January 1	$ 316	$ 254
Incurred liabilities, including acquisitions	55	14
Settled liabilities, including dispositions	(20)	(6)
Accretion expense (included in depreciation, depletion and amortization)	14	12
Revisions of estimates	(25)	42
Ending balance as of December 31	340	316
Asset retirement obligation, current	45	28
Ensign Natural Resources
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Asset retirement obligations	$ 41		$ 41
Gulf Of Mexico
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Revisions of estimates		37
Asset retirement obligation, current		14
Impairments		$ 30

Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Asset Retirement Obligations

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- Definition

The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 25
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-URI https://asc.fasb.org/extlink&oid=116646717&loc=d3e6290-110844

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- Definition

Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
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-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=6392676&loc=d3e7480-110848

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Current portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

+ References

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-Publisher FASB
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Amount of asset retirement obligations incurred during the period.

+ References

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-Publisher FASB
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Amount of asset retirement obligations settled, or otherwise disposed of, during the period. This may include asset retirement obligations transferred to third parties associated with the sale of a long-lived asset.

+ References

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-Publisher FASB
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Amount of increase (decrease) in the asset retirement obligation from changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation.

+ References

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-Publisher FASB
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

The expense recorded to reduce the value of oil and gas assets consisting of proved properties and unproved properties as the estimate of future successful production from these properties is reduced.

+ References

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