Net of Short term assets and liabilties acquired.

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Percent of asset ownership acquired.

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Capitalized costs of proved properties incurred for any combination mineral interests acquisitions; wells and related equipment; support equipment and facilities; and uncompleted wells and equipment and other costs not previously disclosed within this table.

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Capitalized costs of unproved properties incurred for any combination mineral interests acquisitions and other costs not previously disclosed within this table.

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Cost incurred, including capitalized costs and costs charged to expense, in acquisition of oil and gas properties.

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The fair value of assets acquired in noncash investing or financing activities.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Aquisitons (Details) - USD ($)	1 Months Ended	3 Months Ended	12 Months Ended
Aquisitons (Details) - USD ($)	May 31, 2018	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 18, 2018
Business Combinations [Abstract]
Property, Plant and Equipment, Net		$ 45,698,000,000	$ 42,269,000,000	$ 45,698,000,000
Capitalized Costs, Unproved Properties		4,662,000,000	3,980,000,000	4,662,000,000
Capitalized Costs Proved Properties		100,657,000,000	88,284,000,000	100,657,000,000
Inventories Acquired			0	42,000,000	$ 0
Investments and long-term receivables		9,329,000,000	8,687,000,000	9,329,000,000
Asset Retirement Obligation		7,908,000,000	$ 6,206,000,000	$ 7,908,000,000	$ 7,798,000,000
Kuparuk Assets [Member] \| Alaska Segment [Member] \| Operating Segments [Member]
Business Acquisition [Line Items]
Costs Incurred, Acquisition of Oil and Gas Properties, Total	$ 386,000,000	1,490,000,000
Percent Acquired	22.00%
Fair Value of Assets Acquired		1,743,000,000
Business Combinations [Abstract]
Capitalized Costs, Unproved Properties	$ 114,000,000
Capitalized Costs Proved Properties	297,000,000					$ 1,900,000,000
Inventories Acquired	20,000,000	$ 42,000,000
Investments and long-term receivables	14,000,000					15,000,000
Net Working Capital						(100,000,000)
Kuparuk Assets [Member] \| Alaska Segment [Member] \| Operating Segments [Member] \| Asset Retirement Obligation Costs [Member]
Business Combinations [Abstract]
Asset Retirement Obligation	$ 59,000,000					$ 374,000,000