Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
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-Section 45
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

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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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Amount of daily production of the applicable energy source.

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Acquisitions and Dispositions - Assets Sold - Textual (Details)	3 Months Ended			9 Months Ended		12 Months Ended
	Sep. 30, 2021 USD ($)	Mar. 31, 2021 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) d / MBoe	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Gain (loss) on dispositions	$ 2,000,000		$ (3,000,000)	$ 294,000,000	$ 551,000,000
Lower 48 Segment
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Proceeds from asset dispositions	150,000,000
Before-tax gain (loss) on disposition	26,000,000
Production \| d / MBoe				15
Canada and Lower 48 [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Gain (loss) on dispositions	121,000,000			$ 222,000,000		$ 0
Barossa project [Member] \| Asia Pacific [Member] \| Operating Segments [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Before-tax gain (loss) on disposition		$ 200,000,000
Barossa project [Member] \| Asia Pacific [Member] \| Operating Segments [Member] \| Scenario Plan [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Proceeds from asset dispositions						$ 200,000,000
Noncore Exploration Interests in Argentina [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Before-tax gain (loss) on disposition	$ 179,000,000