Impairments	12 Months Ended
Dec. 31, 2019
Impairment Of Long Lived Assets [Abstract]
Impairments	Note 9—Impairments During 2019, 2018 and 2017, we recognized the following before-tax impairment charges: Millions of Dollars 2019 2018 2017 Alaska $ - 20 180 Lower 48 402 63 3,969 Canada 2 9 22 Europe and North Africa 1 (79) 46 Asia Pacific and Middle East - 14 2,384 $ 405 27 6,601 2019 In the Lower 48, we recorded impairments of $ 402 million, primarily related to developed properties in our Niobrara asset which were written down to fair value less costs to sell. See Note 5—Asset Acquisitions and Dispositions, for additional information on this disposition. The charges discussed below, within this section, are included in the “Exploration expenses” line on our consolidated income statement and are not reflected in the table above. In our Lower 48 segment, we recorded a before-tax impairment of $ 141 million for the associated carrying value of capitalized undeveloped leasehold costs due to our decision to discontinue exploration activities related to our Central Louisiana Austin Chalk acreage. 2018 In Alaska, we recorded impairments of $ 20 million primarily due to cancelled projects. In the Lower 48, we recorded impairments of $ 63 million, primarily related to developed properties in our Barnett asset which were written down to fair value less costs to sell, partly offset by a revision to reflect finalized proceeds on a separate transaction. In our Europe and North Africa segment, we recorded a credit to impairment of $ 79 million, primarily due to decreased ARO estimates on fields in the U.K. which have ceased production and were impaired in prior years, partly offset by an increased ARO estimate on a field in Norway which has ceased production. 2017 In Alaska, we recorded impairments of $ 180 million primarily for the associated PP&E carrying value of our small interest in the Point Thomson unit. In the Lower 48, we recorded impairments of $ 3,969 million primarily due to certain developed properties which were written down to fair value less costs to sell. See Note 5—Asset Acquisitions and Dispositions, for additional information on our dispositions. In Canada, we recorded impairments of $ 22 million primarily due to cancelled projects. In Europe and North Africa, we recorded impairments of $ 46 million primarily due to reduced volume forecasts for a field in the U.K. and restructured ownership and a change in commercial premises for a gas processing plant in Norway, partly offset by decreased ARO estimates on fields at or nearing the end of life which were impaired in prior years. In Asia Pacific and Middle East, we recorded impairments of $ 2,384 million, including the impairment of our APLNG investment. For more information, see the “APLNG” section of Note 6—Investments, Loans and Long-Term Receivables. The charges discussed below, within this section, are included in the “Exploration expenses” line on our consolidated income statement and are not reflected in the table above. In our Lower 48 segment, we recorded a before-tax impairment of $ 51 million for the associated carrying value of capitalized undeveloped leasehold costs of Shenandoah in deepwater Gulf of Mexico following the suspension of appraisal activity by the operator. Additionally, we recorded a $ 38 million before-tax impairment for mineral assets primarily due to plan of development changes.

2019

In the Lower 48, we recorded impairments

of $

402

million, primarily related to developed properties

in our

Niobrara asset which were written down to fair value

less costs to sell.

See Note 5—Asset Acquisitions and

Dispositions,

for additional information on this disposition.

The charges discussed below, within this section, are included in the “Exploration

expenses” line on our

consolidated income statement and are not reflected

in the table above.

In our Lower 48 segment, we recorded a before-tax impairment

of $

141

million for the associated carrying

value of capitalized undeveloped leasehold costs

due to our decision to discontinue exploration

activities

related to our Central Louisiana Austin Chalk

acreage.

2018

In Alaska, we recorded impairments of $

million primarily due to cancelled projects.

In the Lower 48, we recorded impairments

of $

million, primarily related to developed properties

in our

Barnett asset which were written down to fair value

less costs to sell, partly offset by a revision to reflect

finalized proceeds on a separate transaction.

In our Europe and North Africa segment, we recorded

a credit to impairment of $

million, primarily due to

decreased ARO estimates on fields in the

U.K. which have ceased production and

were impaired in prior years,

partly offset by an increased ARO estimate on a field

in Norway which has ceased production.

2017

In Alaska, we recorded impairments of $

180

million primarily for the associated PP&E

carrying value of our

small interest in the Point Thomson unit.

In the Lower 48, we recorded impairments

of $

3,969

million primarily due to certain developed

properties

which were written down to fair value less costs

to sell.

See Note 5—Asset Acquisitions and Dispositions, for

additional information on our dispositions.

In Canada, we recorded impairments of $

million primarily due to cancelled projects.

In Europe and North Africa, we recorded impairments

of $

million primarily due to reduced volume

forecasts for a field in the U.K. and restructured ownership

and a change in commercial premises for a gas

processing plant in Norway, partly offset by decreased ARO estimates on fields at or

nearing the end of life

which were impaired in prior years.

In Asia Pacific and Middle East, we recorded impairments

of $

2,384

million, including the impairment of our

APLNG investment.

For more information, see the “APLNG”

section of Note 6—Investments, Loans and

Long-Term Receivables.

The charges discussed below, within this section, are included in the “Exploration

expenses” line on our

consolidated income statement and are not reflected

in the table above.

In our Lower 48 segment, we recorded a before-tax impairment

of $

million for the associated carrying

value of capitalized undeveloped leasehold costs

of Shenandoah in deepwater Gulf of Mexico

following the

suspension of appraisal activity by the operator.

Additionally, we recorded a $

million before-tax

impairment for mineral assets primarily

due to plan of development changes.