Debt (Details Textual) $ in Millions	3 Months Ended
Mar. 31, 2017 USD ($)	Mar. 31, 2016 USD ($)
Debt Instrument [Line Items]
Repayments of Debt	$ 839	$ 64
ShortTermBorrowings [Abstract]
Maturity period of commercial paper (in days)	P90D
Letters of credit issued	$ 266
Debt (Textual) [Abstract]
Classification of short-term debt as long-term debt	$ 0
Debt to capital ratio	0.65
Floating Rate Notes due 2019 [Member]
Debt Instrument [Line Items]
Repayments of Debt	$ 805
Remaining Amount of Debt	$ 645
Debt Instrument, Maturity Date	Mar. 18, 2019
Marine Terminal Revenue Refunding Bonds due through 2035
Debt Instrument [Line Items]
Debt at face value	$ 283
Debt Instrument, Maturity Date	Dec. 31, 2035
Revolving Credit Facilities [Member]
ShortTermBorrowings [Abstract]
Total amount under revolving credit facilities	$ 6,750
Letters of credit issued	0
Credit facilities remaining after commercial paper outstanding and issuance of letters of credit	6,750
ConocoPhillips [Member]
Debt Instrument [Line Items]
Repayments of Debt	805	$ 0
ShortTermBorrowings [Abstract]
Commercial paper program	6,250
ConocoPhillips Qatar Funding Ltd. [Member]
ShortTermBorrowings [Abstract]
Commercial paper program	500
Commercial paper outstanding	$ 0

Commercial paper program

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- Definition

Debt textual.

+ References

No definition available.

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Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19)(a)(3))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(13)(2))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

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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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No definition available.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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- Definition

Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

+ References

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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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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Indebtedness divided by net capital.

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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Amount of a short-term obligation that has been excluded from current liabilities in the balance sheet because of a refinancing of the obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1927-112601

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Description of the short-term debt arrangement, and disclosures pertaining to the underlying arrangements, including repayment terms, interest rates, restrictions on assets and activities, debt covenants, and other matters important to users of the financial statements.

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