Fair Value Measurements (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Embedded derivatives
Goodwill impairment	$ 1,200
Oil and gas segment
Embedded derivatives
Impairment and related charges	581
Midstream and Marketing \| Anadarko
Embedded derivatives
Goodwill		$ 1,200
Oman, Bolivia and the Gulf of Mexico
Embedded derivatives
Impairment and related charges	293
Gulf of Mexico
Embedded derivatives
Impairment and related charges	$ 241
Level 3 \| Measurement Input, Discount Rate
Embedded derivatives
Risk adjusted discount rate	10.00%
Recurring \| Accrued liabilities
Embedded derivatives
Netting and Collateral	$ 0	0
Recurring \| Accrued liabilities \| Total Fair Value
Embedded derivatives
Embedded derivatives	105	40
Recurring \| Accrued liabilities \| Level 1
Embedded derivatives
Embedded derivatives	0	0
Recurring \| Accrued liabilities \| Level 2
Embedded derivatives
Embedded derivatives	105	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	0
Recurring \| Deferred credits and other liabilities - other \| Total Fair Value
Embedded derivatives
Embedded derivatives	67	49
Recurring \| Deferred credits and other liabilities - other \| Level 1
Embedded derivatives
Embedded derivatives	0	0
Recurring \| Deferred credits and other liabilities - other \| Level 2
Embedded derivatives
Embedded derivatives	67	49
Recurring \| Deferred credits and other liabilities - other \| Level 3
Embedded derivatives
Embedded derivatives	$ 0	$ 0

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