Reduction to previous award.

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Revised amount awarded from other party in judgment or settlement of litigation.

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The duration from whence interests were sold.

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

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

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

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No definition available.

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Amount awarded from other party in judgment or settlement of litigation.

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No definition available.

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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.

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The value (monetary amount) of the award the plaintiff seeks in the legal matter.

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The total number of new claims filed pertaining to a loss contingency during the period.

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Description of the terms of a settlement agreement which resolved the legal matter, including the nature of the consideration, timing of payment, and the nature of rights obtained or lost (for example, but not limited to, patent, trademark, copyright, license and franchise rights).

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Cash received for the settlement of litigation during the current period.

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Contingencies and Commitments - Textual (Details) $ in Millions			1 Months Ended			9 Months Ended	12 Months Ended	35 Months Ended
	May 10, 2021 USD ($)	Aug. 02, 2019 USD ($)	Mar. 31, 2019 USD ($)	Aug. 31, 2018 USD ($)	Apr. 30, 2018 USD ($)	Sep. 30, 2021 USD ($)	Dec. 31, 2017 Lawsuits	Jun. 30, 2021 USD ($)	Dec. 31, 2020 USD ($)	Aug. 29, 2019 USD ($)
Loss Contingencies [Line Items]
Total environmental accrual included in balance sheet						$ 191			$ 180
Letters of Credit Outstanding, Amount						$ 281
Performance Guarantee [Member]
Loss Contingencies [Line Items]
Loss Contingency Damages Sought Value	$ 200
Several Louisiana parishes and the State of Louisiana against oil and gas companies [Member]
Loss Contingencies [Line Items]
Loss Contingency, New Claims Filed, Number \| Lawsuits							43
Several Louisiana parishes and the State of Louisiana against oil and gas companies [Member] \| ConocoPhillips Entities [Member]
Loss Contingencies [Line Items]
Loss Contingency, New Claims Filed, Number \| Lawsuits							22
Outer Continental Shelf Lease [Member] \| Phillips Petroleum Company [Member]
Loss Contingencies [Line Items]
Ownership percentage in equity investment						25.00%
Sale of interest, duration						30 years
Venezuela \| ConocoPhillips Versus Petroleos de Venezuela ICISD [Member]
Loss Contingencies [Line Items]
Litigation Settlement, Amount Awarded from Other Party			$ 8,700
Litigation Award Reduction										$ 227
Litigation Settlement Amount Awarded From Other Party Revised						$ 8,500
Venezuela \| ConocoPhillips vs Petroleos De Venezuela ICC [Member]
Loss Contingencies [Line Items]
Litigation Settlement, Amount Awarded from Other Party		$ 33		$ 500	$ 2,000
Loss Contingency, Settlement Agreement, Terms						In August 2018, ConocoPhillips entered into a settlement with PDVSA to recover the full amount of this ICC award, plus interest through the payment period, including initial payments totaling approximately $500 million within a period of 90 days from the time of signing of the settlement agreement. The balance of the settlement is to be paid quarterly over a period of four and a half years.
Cash Proceeds from Legal Settlements								$ 766
US and Canada [Member] \| Cleanup Remediation Activities [Member]
Loss Contingencies [Line Items]
Loss Contingency, Settlement Agreement, Terms						P30Y