Name:	cop_NetPurchasesSalesOfShortTermInvestments
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Cash outflow related to foreigh currecy transaction for derivatives.

No definition available.

Name:	cop_PaymentsForForeignCurrencyDerivativeInstrumentsNotDesignatedAsHedgingInstruments
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Supplemental cash flow information.

No definition available.

Name:	cop_SupplementalCashFlowsInformationAbstract
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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.

No definition available.

Name:	us-gaap_DerivativeInstrumentsGainLossLineItems
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Data Type:	xbrli:stringItemType
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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586

Name:	us-gaap_IncomeTaxesPaidNet
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The amount of cash paid for interest during the period net of cash paid for interest that is capitalized.

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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.

No definition available.

Name:	us-gaap_LongLivedAssetsHeldForSaleLineItems
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Data Type:	xbrli:stringItemType
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Amount of cash (inflow) outflow from investing activities classified as other.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3098-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3095-108585

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- References

No definition available.

Name:	us-gaap_PaymentsForProceedsFromShortTermInvestmentsAlternativeAbstract
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Data Type:	xbrli:stringItemType
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The cash outflow for securities or other assets acquired, which qualify for treatment as an investing activity and are to be liquidated, if necessary, within the current operating cycle. Includes cash flows from securities classified as trading securities that were acquired for reasons other than sale in the short-term.

Name:	us-gaap_PaymentsToAcquireShortTermInvestments
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Data Type:	xbrli:monetaryItemType
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The cash inflow from sales of all investments, including securities and other assets, having ready marketability and intended by management to be liquidated, if necessary, within the current operating cycle. Includes cash flows from securities classified as trading securities that were acquired for reasons other than sale in the short-term.