Segment Disclosures - Capital Expenditures and Interest (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Capital Expenditures and Investments
Consolidated capital expenditures and investments	$ 6,636	$ 6,750	$ 4,591
Interest Income and Expense
Interest income	166	97	112
Interest and debt expense	778	735	1,098
Corporate, Non-Segment [Member]
Capital Expenditures and Investments
Consolidated capital expenditures and investments	61	190	63
Interest Income and Expense
Interest income	149	80	101
Interest and debt expense	778	735	1,098
Alaska Segment [Member] \| Operating Segments [Member]
Capital Expenditures and Investments
Consolidated capital expenditures and investments	1,513	1,298	815
Interest Income and Expense
Interest income	0	0	0
Lower 48 Segment [Member] \| Operating Segments [Member]
Capital Expenditures and Investments
Consolidated capital expenditures and investments	3,394	3,184	2,136
Interest Income and Expense
Interest income	0	0	0
Canada Segment [Member] \| Operating Segments [Member]
Capital Expenditures and Investments
Consolidated capital expenditures and investments	368	477	202
Interest Income and Expense
Interest income	0	0	0
Europe and North Africa Segment [Member] \| Operating Segments [Member]
Capital Expenditures and Investments
Consolidated capital expenditures and investments	708	877	872
Interest Income and Expense
Interest income	2	2	2
Asia Pacific and Middle East Segment [Member] \| Operating Segments [Member]
Capital Expenditures and Investments
Consolidated capital expenditures and investments	584	718	482
Interest Income and Expense
Interest income	15	15	9
Other International Segment [Member] \| Operating Segments [Member]
Capital Expenditures and Investments
Consolidated capital expenditures and investments	8	6	21
Interest Income and Expense
Interest income	$ 0	$ 0	$ 0

Capital expenditures and investments.

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Segment reporting information capital expenditures and investments.

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Interest and debt related expenses associated with nonoperating financing activities of the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 20
-Section 50
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Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7(b))
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599

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