v2.4.0.6

Debt - Additional Information (Detail) (USD $) | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2011 | Aug. 31, 2011 | Dec. 31, 2010
Short-term Debt [Line Items] |  |  |
Maturities of long-term borrowings net of unamortized premiums and discounts in 2012 | $ 1,013,000,000 |  |
Maturities of long-term borrowings net of unamortized premiums and discounts in 2013 | 1,275,000,000 |  |
Maturities of long-term borrowings net of unamortized premiums and discounts in 2014 | 1,527,000,000 |  |
Maturities of long-term borrowings net of unamortized premiums and discounts in 2015 | 1,571,000,000 |  |
Maturities of long-term borrowings net of unamortized premiums and discounts in 2016 | 2,364,000,000 |  |
Classification of short-term debt as long-term debt | 1,058,000,000 |  |
Total amount under revolving credit facilities |  | 8,000,000,000 |
Revolving credit facilities may be used as support for letters of credit | 750,000,000 |  |
Minimum limit of debt for cross default provision | 200,000,000 |  |
Maturity period of commercial paper (in days) | 90 |  |
Direct outstanding borrowings under the revolving credit facilities | 0 |  | 0
Letters of credit issued under revolving credit facilities | 1,954,000,000 |  |
Commercial paper outstanding | 1,128,000,000 |  | 1,182,000,000
Credit facilities remaining after commercial paper outstanding and issuance of letters of credit | 6,800,000,000 |  |
Revolving Credit Facility [Member] |  |  |
Short-term Debt [Line Items] |  |  |
Letters of credit issued under revolving credit facilities | 40,000,000 |  |
ConocoPhillips [Member] |  |  |
Short-term Debt [Line Items] |  |  |
ConocoPhillips Commercial Paper Program | 6,350,000,000 |  |
ConocoPhillips Qatar Funding Ltd [Member] |  |  |
Short-term Debt [Line Items] |  |  |
ConocoPhillips Commercial Paper Program | 1,500,000,000 |  |
9.375% Notes due 2011 [Member] |  |  |
Short-term Debt [Line Items] |  |  |
Note repaid at its maturity | 328,000,000 |  |
6.50% Notes due 2011 [Member] |  |  |
Short-term Debt [Line Items] |  |  |
Note repaid at its maturity | 500,000,000 |  |
Old Revolving Credit Facilities [Member] |  |  |
Short-term Debt [Line Items] |  |  |
Total amount under revolving credit facilities |  | 7,850,000,000 |
Old revolving credit facility expiring in September 2012 [Member] |  |  |
Short-term Debt [Line Items] |  |  |
Total amount under revolving credit facilities | 7,350,000,000 |  |
Credit facility expiring in August 2016 [Member] |  |  |
Short-term Debt [Line Items] |  |  |
Total amount under revolving credit facilities | 7,500,000,000 |  |
Revolving credit facility expiring in July 2012 [Member] |  |  |
Short-term Debt [Line Items] |  |  |
Total amount under revolving credit facilities | $ 500,000,000 |  |

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- Definition 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 Statement of Financial Accounting Standard (FAS) -Number 6 -Paragraph 15 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: 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 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19 -Subparagraph b -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 129 -Paragraph 2, 4 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 4: 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(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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