v2.4.0.6

Financial Instruments and Derivative Contracts - Additional Information (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2011 | Dec. 31, 2010 | Jun. 30, 2010 4.6% Bonds [Member]
Debt Instrument [Line Items] |  |  |  |
Amount converted by interest rate swap execution |  |  |  | $ 500
Interest rate of fixed bonds |  |  |  | 4.60%
Payment term of receivables | 30 days or less |  |  |
Aggregate fair value of all derivative instruments in a liability position | 237 |  |  |
Collateral was posted for derivative instruments in a liability position | 3 |  |  |
Additional collateral, either in the form of cash or letters of credit | 234 |  |  |
Carrying value of share investment in LUKOIL |  | 1,083 | [1] |
Closing price per share on London Stock Exchange |  | $ 56.50 |  |
Fixed-rate on joint venture acquisition obligation | 5.30% |  |  |
Effective yield rate | 1.24% | 1.87% |  |
Obligations to return cash collateral | 0 | 5 |  |
Rights to reclaim cash collateral | $ 244 | $ 324 |  |
[1] | Certain amounts have been restated to reflect a prior period adjustment. See Note 21-Accumulated Other Comprehensive Income, in the Notes to Consolidated Financial Statements.

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- Definition The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 44D -Subparagraph c -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 815 -SubTopic 10 -Section 50 -Paragraph 4H -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624258-113959 + Details
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- Definition The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4H -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624258-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 44D -Subparagraph b -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. + Details
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