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Equity Method Investment, Charges at Fair Value

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Goodwill Impairment Charges, Fair Value

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Oil and Gas, Operating and Capital Cost Estimates, Percentage

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Oil And Gas Properties, Discontinued Operations, Net Charges at Fair Value

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Oil And Gas Properties, Proved, Charges at Fair Value

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Oil And Gas Properties, Unproved, Charges at Fair Value

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Oil and Gas, Unweighted Arithmetic Average Price, Period

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Oil and Gas, Unweighted Arithmetic Average Sale Price

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Oil and Gas Properties, Measurement Input

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Pre-tax Impairment and Related Charges, Domestic Undeveloped Leases

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Sales price per unit of oil and gas produced.

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Fair value of asset associated with 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, and right to receive cash collateral under master netting arrangements.

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Fair value as of the balance sheet date of the embedded derivative or group of embedded derivatives classified as a liability.

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This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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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.

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FAIR VALUE MEASUREMENTS (Details) $ in Millions	3 Months Ended			9 Months Ended	12 Months Ended
FAIR VALUE MEASUREMENTS (Details) $ in Millions	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($) $ / MillionCubicFeet $ / Barrel	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Embedded derivatives
Impairment and related charges		$ 8,600				$ 285
Goodwill derecognized			$ 1,200
Pre-tax impairment and related charges on domestic undeveloped leases						285
WES
Embedded derivatives
Goodwill derecognized			1,200
Impairment of equity method investment	$ 2,700					1,000
Other-than-temporary impairment loss	$ 2,700			$ 2,700
Low end of range
Embedded derivatives
Operating and capital cost estimates, percentage					1.00%
Operating and capital cost estimates (in dollars per barrel) \| $ / Barrel					50
High end of range
Embedded derivatives
Operating and capital cost estimates, percentage					2.00%
Operating and capital cost estimates (in dollars per barrel) \| $ / Barrel					60
Oil
Embedded derivatives
Sales price (dollars per barrel) \| $ / Barrel					62.42
Unweighted arithmetic average price (in dollars per barrel) \| $ / Barrel					59.17
Unweighted arithmetic average price, period					15 years
Oil \| Low end of range
Embedded derivatives
Sales price (dollars per barrel) \| $ / Barrel					40
Oil \| High end of range
Embedded derivatives
Sales price (dollars per barrel) \| $ / Barrel					70
Natural Gas
Embedded derivatives
Unweighted arithmetic average price (in dollars per barrel) \| $ / MillionCubicFeet					3.13
Unweighted arithmetic average price, period					15 years
Natural Gas \| Low end of range
Embedded derivatives
Sales price (dollars per barrel) \| $ / MillionCubicFeet					2.00
Natural Gas \| High end of range
Embedded derivatives
Sales price (dollars per barrel) \| $ / MillionCubicFeet					3.60
Oman, Bolivia and the Gulf of Mexico
Embedded derivatives
Impairment and related charges			293
Gulf of Mexico
Embedded derivatives
Impairment and related charges			241		$ 1,200
Algeria Oil and Gas Proved Properties
Embedded derivatives
Impairment and related charges					900
Qatar ISSD
Embedded derivatives
Impairment and related charges						39
Pre-tax impairment charges						39
Qatar ISND and ISSD
Embedded derivatives
Impairment and related charges							$ 416
Level 2 \| Domestic Onshore Unproved Acreage
Embedded derivatives
Impairment and related charges					$ 4,300
Level 3 \| Measurement Input, Weighted Average Cost of Capital
Embedded derivatives
Discount rate					10.00%
Recurring \| Accrued liabilities
Embedded derivatives
Netting and Collateral					$ 0	0
Recurring \| Accrued liabilities \| Fair Value
Embedded derivatives
Embedded derivatives					64	40
Recurring \| Accrued liabilities \| Level 1
Embedded derivatives
Embedded derivatives					0	0
Recurring \| Accrued liabilities \| Level 2
Embedded derivatives
Embedded derivatives					64	40
Recurring \| Accrued liabilities \| Level 3
Embedded derivatives
Embedded derivatives					0	0
Recurring \| Deferred credits and other liabilities - other
Embedded derivatives
Netting and Collateral						0
Recurring \| Deferred credits and other liabilities - other \| Fair Value
Embedded derivatives
Embedded derivatives						49
Recurring \| Deferred credits and other liabilities - other \| Level 1
Embedded derivatives
Embedded derivatives						0
Recurring \| Deferred credits and other liabilities - other \| Level 2
Embedded derivatives
Embedded derivatives						49
Recurring \| Deferred credits and other liabilities - other \| Level 3
Embedded derivatives
Embedded derivatives						0
Non recurring
Embedded derivatives
Goodwill impairment					1,153
Oil and gas properties - proved					2,436
Oil and gas properties - unproved					4,591
Oil and gas properties - discontinued operations, net					2,191
WES equity investment					2,673
Ghana Assets
Embedded derivatives
Impairment and related charges					$ 2,200
Ghana Assets \| Discontinued Operations, Held-for-sale
Embedded derivatives
Impairment and related charges		2,200
Impairment and related charges, net of tax		1,400
Oil and gas
Embedded derivatives
Impairment and related charges		$ 6,400	$ 581
Midstream and marketing
Embedded derivatives
Impairment and related charges							$ 100
Goodwill						$ 1,200