v2.4.0.6

Debt (Details Textual) (USD $)	3 Months Ended	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2012	Dec. 31, 2011
Commercial Paper Programs (Textual) [Abstract]
Total amount under revolving credit facilities	$ 7,500,000,000	$ 7,500,000,000
Debt (Textual) [Abstract]
Maturity period of commercial paper (in days)		90
Letters of credit issued under revolving credit facilities	0	0	40,000,000
Commercial paper outstanding	1,540,000,000	1,540,000,000	1,128,000,000
Credit facilities remaining after commercial paper outstanding and issuance of letters of credit	6,000,000,000	6,000,000,000
Classification of short-term debt as long-term debt	967,000,000
Net loss on redemption of outstanding bond		79,000,000
4.4% Notes Due 2013 [Member]
Extinguishment Of Debt Disclosures [Abstract]
Stated percentage of debt	4.40%	4.40%
Debt instruments repaid		400,000,000
4.75% Notes Due 2014 [Member]
Extinguishment Of Debt Disclosures [Abstract]
Stated percentage of debt	4.75%	4.75%
Debt instruments repaid		1,100,000,000
Original amount of debt instrument	1,500,000,000	1,500,000,000
ConocoPhillips [Member]
Commercial Paper Programs (Textual) [Abstract]
ConocoPhillips Commercial Paper Program	6,350,000,000	6,350,000,000
ConocoPhillips Qatar Funding Ltd. [Member]
Commercial Paper Programs (Textual) [Abstract]
ConocoPhillips Commercial Paper Program	$ 1,150,000,000	$ 1,150,000,000

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Commercial paper program.

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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.

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The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

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Interest rate stated in the contractual debt agreement.

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Gross amount of debt extinguished.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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

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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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