Reduction to previous award.

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

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Total payment agreement at a given point in time related to an amount awarded from other party in judgment or settlement of litigation.

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Settlement Amount Awarded To Other Party Through Third Party.

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

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

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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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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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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of the unrecorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Contingencies and Commitments (Details) - USD ($) $ in Millions	1 Months Ended						12 Months Ended
	Sep. 30, 2019	Aug. 31, 2019	Mar. 31, 2019	Apr. 30, 2018	Dec. 31, 2017	Feb. 28, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Aug. 29, 2019
Loss Contingencies [Line Items]
Letters of Credit Outstanding, Amount							$ 277.0
Long-Term Throughput Agreements and Take-or-Pay Agreements [Abstract]
Payments under Long-Term Throughput Agreements And Take-or-Pay Agreements, Due within one year							7.0
Payments under Long-Term Throughput Agreements And Take-or-Pay Agreements, Due in Second Year							7.0
Payments under Long-Term Throughput Agreements And Take-or-Pay Agreements, Due in Third Year							7.0
Payments under Long-Term Throughput Agreements And Take-or-Pay Agreements, Due in Fourth Year							7.0
Payments under Long-Term Throughput Agreements And Take-or-Pay Agreements, Due in Fifth Year							7.0
Payments under Long-Term Throughput Agreements And Take-or-Pay Agreements, Due after Fifth Year							57.0
Total payments under Long-Term Throughput Agreements and Take-or-Pay Agreements					$ 43.0		25.0	$ 39.0	$ 43.0
Ecuador \| Cleanup Remediation Activities [Member] \| Penrenco Ecuador Limited [Member]
Loss Contingencies [Line Items]
Settlement Amount Awarded To Other Party Through Third Party	$ 54.0
Burlington Resources Inc Vs The Republic Of Ecuador [Member]
Loss Contingencies [Line Items]
Cash Proceeds from Legal Settlements								262.0	$ 75.0
Burlington Resources Inc Vs The Republic Of Ecuador [Member] \| Burlington Resources Inc [Member] \| Ecuador
Loss Contingencies [Line Items]
Litigation Settlement, Amount Awarded from Other Party						$ 380.0
Litigation Settlement, Amount Awarded to Other Party						$ 42.0
Cash Proceeds from Legal Settlements				$ 262.0	75.0
Settlement Agreement Payment Installment Total					$ 337.0
ConocoPhillips Vs Petroleos de Venezuela SA [Member]
Loss Contingencies [Line Items]
Cash Proceeds from Legal Settlements							$ 330.0	$ 430.0
ConocoPhillips Vs Petroleos de Venezuela SA [Member] \| Venezuela
Loss Contingencies [Line Items]
Litigation Settlement, Amount Awarded from Other Party			$ 8,700.0
Litigation Settlement Amount Awarded From Other Party Revised										$ 8,500.0
Litigation Award Reduction										$ 227.0
Loss Contingency Settlement Agreement Terms							under their agreements in connection with the expropriation of the projects and other pre-expropriation fiscal measures. 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.
ConocoPhillips Versus Petroleos De Venezuela 2 [Member] \| Venezuela
Loss Contingencies [Line Items]
Litigation Settlement, Amount Awarded from Other Party				$ 2,000.0
Cash Proceeds from Legal Settlements							$ 754.0
Conoco Phillips Versus Petroleos DeVenezuela 3 [Member] \| Venezuela
Loss Contingencies [Line Items]
Litigation Settlement, Amount Awarded from Other Party		$ 55.0