Guarantees - Narrative (Details) $ in Millions	6 Months Ended
Jun. 30, 2023 USD ($)
APLNG
Guarantor Obligations [Line Items]
Ownership percentage in equity investment	47.50%
Finance Reserve Guarantee \| APLNG
Guarantor Obligations [Line Items]
Guarantor obligations, remaining term	8 years
Maximum potential amount of future payments	$ 210
Guarantor obligations, current carrying value	14
Max Potential Future Payments Reckless Breach \| APLNG
Guarantor Obligations [Line Items]
Maximum potential amount of future payments	1,300
Max Potential Future Payments Pro-rata Share \| APLNG
Guarantor Obligations [Line Items]
Maximum potential amount of future payments	740
Continued Development \| APLNG
Guarantor Obligations [Line Items]
Maximum potential amount of future payments	390
Guarantor obligations, current carrying value	$ 29
Continued Development \| APLNG \| Minimum
Guarantor Obligations [Line Items]
Guarantor obligations, term	14 years
Continued Development \| APLNG \| Maximum
Guarantor Obligations [Line Items]
Guarantor obligations, term	22 years
Other Guarantees
Guarantor Obligations [Line Items]
Maximum potential amount of future payments	$ 600
Guarantor obligations, current carrying value	$ 0
Other Guarantees \| Minimum
Guarantor Obligations [Line Items]
Guarantor obligations, term	2 years
Other Guarantees \| Maximum
Guarantor Obligations [Line Items]
Guarantor obligations, term	4 years
Joint Venture Obligation Guarantee \| QG8 and QG12
Guarantor Obligations [Line Items]
Guarantor obligations, current carrying value	$ 14
Guarantor Obligations, Term	30 years
Indemnifications
Guarantor Obligations [Line Items]
Guarantor obligations, current carrying value	$ 20

Guarantee Obligations, Period

No definition available.

Name:	cop_GuaranteeObligationsPeriod
Namespace Prefix:	cop_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Guarantor Obligations, Remaining Term

+ References

No definition available.

+ Details

Name:	cop_GuarantorObligationsRemainingTerm
Namespace Prefix:	cop_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Guarantor Obligations, Term

+ References

No definition available.

+ Details

Name:	cop_GuarantorObligationsTerm
Namespace Prefix:	cop_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 323
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481687/323-10-50-3

+ Details

Name:	us-gaap_EquityMethodInvestmentOwnershipPercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482425/460-10-50-4

+ Details

Name:	us-gaap_GuaranteeObligationsCurrentCarryingValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482425/460-10-50-4

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482425/460-10-50-4

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482425/460-10-50-4

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482425/460-10-50-4

+ Details

Name:	us-gaap_GuaranteeObligationsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482425/460-10-50-4

+ Details

Name:	us-gaap_GuaranteeObligationsMaximumExposure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=cop_AustraliaPacificAplngMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_GuaranteeObligationsByNatureAxis=cop_FinanceReserveGuaranteeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_GuaranteeObligationsByNatureAxis=cop_MaxPotentialFuturePaymentsRecklessBreachMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_GuaranteeObligationsByNatureAxis=cop_MaxPotentialFuturePaymentsProrataShareMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_GuaranteeObligationsByNatureAxis=cop_AplngContinuedDevelopmentMemberMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_GuaranteeObligationsByNatureAxis=cop_OtherGuaranteesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_GuaranteeObligationsByNatureAxis=cop_JointVentureObligationGuaranteeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=cop_QatarLiquefiedGasCompanyLimited8And12Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_GuaranteeObligationsByNatureAxis=us-gaap_IndemnificationGuaranteeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: