| **Selected Quarterly Financial Data (Unaudited)** | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
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| **Selected Quarterly Financial Data (Unaudited)** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| Selected Quarterly Financial Data (Unaudited)     | NOTE 15 – SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED)  (Millions of dollars)            2011   First quarter  Second quarter  Third quarter  Fourth quarter Total revenues $640  $675  $668  $662 Profit before taxes $115  $152  $126  $111 Profit $83  $107  $93  $95                     2010  First quarter  Second quarter  Third quarter  Fourth quarter Total revenues $631  $648  $640  $633 Profit before taxes $71  $95  $89  $74 Profit $53  $82  $73  $70                     2009   First quarter  Second quarter  Third quarter  Fourth quarter Total revenues $681  $700  $676  $657 Profit before taxes $71  $122  $80  $47 Profit $51  $89  $76  $43                    |

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| - Definition
This element can be used to disclose the entire quarterly financial data disclosure in the annual financial statements as a single block of text.  The disclosure includes a tabular presentation of financial information for each fiscal quarter for the current and previous year, including revenues, gross profit, income (loss) before extraordinary items and cumulative effect of a change in accounting principle and earnings per share data. It also includes an indication if the information in the note is unaudited, comments on the aggregate effect of year-end adjustments, and an explanation of matters or transactions that affect comparability or are pertinent to an understanding of the information furnished. Alternatively, the details of this disclosure can be reported using the elements in this group, or by using other taxonomy elements and applying the appropriate quarterly date and period contexts when creating an instance document. For example, the element for "Interest and Dividend Income, Operating" may be used by financial institutions from the Statement of Income, applying the appropriate quarterly date and period context when creating an instance document.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 6 -Section G -Subsection 1Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 28 -Paragraph 23, 24Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 28 -Paragraph 30 -Subparagraph a-jReference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K (SK) -Number 229 -Section 302 -Paragraph a
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