Dispositions and Other Transactions - Summary of Revenues and Costs from Discontinued Operations (Details) - Anadarko's Africa Assets - Discontinued Operations, Disposed of by Sale $ in Millions	3 Months Ended
Mar. 31, 2020 USD ($)
Revenues and other income
Net sales	$ 332
Costs and other deductions
Oil and gas lease operating expense	46
Transportation expense	7
Taxes other than on income	43
Fair value adjustment on assets held for sale	139
Other	16
Costs and other deductions, net	251
Income before income taxes	81
Income tax expense	(81)
Discontinued operations, net of tax	$ 0

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