v2.4.0.6

Financial Instruments and Derivative Contracts - Commodity Derivative and Financial Instruments (Detail) (USD $) In Millions, unless otherwise specified | Dec. 31, 2011 | Dec. 31, 2010
--- | --- | ---
Financial Assets |  |  |
Investment in LUKOIL |  | $ 1,083 | [1]
Fair Value [Member] | Foreign currency exchange derivatives [Member] |  |  |
Financial Assets |  |  |
Foreign currency exchange derivatives | 13 | 15 |
Financial Liabilities |  |  |
Foreign Currency Derivative Instruments Not Designated as Hedging Instruments, Liability at Fair Value | 23 | 9 |
Fair Value [Member] | Interest rate derivatives [Member] |  |  |
Financial Assets |  |  |
Interest rate derivatives | 31 | 20 |
Fair Value [Member] | Commodity Contract [Member] |  |  |
Financial Assets |  |  |
Price Risk Derivative Assets, at Fair Value | 814 | 624 |
Financial Liabilities |  |  |
Price Risk Derivative Liabilities, at Fair Value | 446 | 426 |
Fair Value [Member] | LUKOIL Investment [Member] |  |  |
Financial Assets |  |  |
Investment in LUKOIL at fair value |  | 1,083 |
Fair Value [Member] | Total debt, excluding capital leases [Member] |  |  |
Financial Liabilities |  |  |
Total debt, excluding capital leases | 27,065 | 26,144 |
Fair Value [Member] | Joint Venture Acquisition Obligation [Member] |  |  |
Financial Liabilities |  |  |
Joint venture acquisition obligation at fair value | 4,820 | 5,600 |
Carrying Amount [Member] | Foreign currency exchange derivatives [Member] |  |  |
Financial Assets |  |  |
Foreign currency exchange derivatives | 13 | 15 |
Financial Liabilities |  |  |
Foreign Currency Derivative Instruments Not Designated as Hedging Instruments, Liability at Fair Value | 23 | 9 |
Carrying Amount [Member] | Interest rate derivatives [Member] |  |  |
Financial Assets |  |  |
Interest rate derivatives | 31 | 20 |
Carrying Amount [Member] | Commodity Contract [Member] |  |  |
Financial Assets |  |  |
Price Risk Derivative Assets, at Fair Value | 814 | 624 |
Financial Liabilities |  |  |
Price Risk Derivative Liabilities, at Fair Value | 446 | 426 |
Carrying Amount [Member] | LUKOIL Investment [Member] |  |  |
Financial Assets |  |  |
Investment in LUKOIL |  | 1,083 |
Carrying Amount [Member] | Total debt, excluding capital leases [Member] |  |  |
Financial Liabilities |  |  |
Total debt, excluding capital leases, carrying amount | 22,592 | 23,553 |
Carrying Amount [Member] | Joint Venture Acquisition Obligation [Member] |  |  |
Financial Liabilities |  |  |
Joint venture acquisition obligation at carrying value | $ 4,314 | $ 5,009 |
[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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