Contingencies and commitments.

No definition available.

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- Definition

Expected years to incur the majority of expenditures.

+ References

No definition available.

+ Details

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- Definition

Separate decision finding Ecuador to be entitled to limited environmental and infrastructure impacts associated with the operations.

+ References

No definition available.

+ Details

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- Definition

Total costs accrued as of the balance sheet date for environmental loss contingencies.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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- Definition

Amount of judgment or settlement awarded to (against) the entity in respect of litigation.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Identifies the named defendant in a lawsuit.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
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- Definition

Identifies the plaintiff in the lawsuit.

+ References

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- Details

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- Details

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- Details

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Contingencies and Commitments (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended
	Feb. 28, 2017	Mar. 31, 2017	Dec. 31, 2016
Contingencies and Commitments (Textual) [Abstract]
Total environmental accrual included in balance sheet		$ 260	$ 247
Expected years to incur the majority of expenditures		30 years
Letters of credit that secure performance obligations		$ 266
Burlington Resources, Inc [Member] \| ECUADOR \| Oil and Gas Properties [Member] \| Confiscated Crude Oil Production [Member]
Loss Contingencies [Line Items]
Loss Contingency, Name of Plaintiff		Burlington Resources, Inc
Loss Contingency, Name of Defendant		The Republic of Ecuador
Litigation Settlement Amount	$ 380
Litigation Settlement Amount, Seperate Seetlement to Defendent, Environemental and Infrastructure Impacts	$ 42