v2.4.0.6

Income Taxes - Additional Information (Detail) (USD $) In Millions, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009
Schedule Of Income Taxes [Line Items] |  |  |  |  |
Deferred taxes Included in current assets | $ 788 |  | $ 562 |  |
Deferred taxes Included in long-term assets | 183 |  | 160 |  |
Deferred taxes Included in current liabilities | 9 |  | 21 |  |
Deferred taxes Included in long-term liabilities | 18,040 | [1] | 17,320 | [1] |
Increase (decrease) in valuation allowance | 87 |  |  |  |
Decrease in valuation allowance | 87 |  |  |  |
Increase in valuation allowance | 174 |  |  |  |
Income considered to be permanently reinvested in foreign subsidiaries and foreign corporate joint ventures | 4,227 |  | 4,134 |  |
Unrecognized tax benefits that if recognized, would affect effective tax rate | 815 |  | 914 |  | 931
Accrued liabilities for interest and penalties | 141 |  | 171 |  | 166
Interest and penalties affecting earnings | 10 |  | 2 |  | 18
Supplementary UK Corporate Rate, before change | 20.00% |  |  |  |
Supplementary UK Corporate Rate, after change | 32.00% |  |  |  |
Overall UK Corporate Rate Before Change | 50.00% |  |  |  |
Overall UK Corporate Rate, after change | 62.00% |  |  |  |
Foreign Income Tax Expense Total, related to new rate | 316 |  |  |  |
Foreign Income Tax Expense Deferred, related to new rate | 106 |  |  |  |
Foreign Income Tax Expense Current, related to new rate | $ 210 |  |  |  |
[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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