| **Short-Term Borrowings** | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
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| **Short-Term Borrowings** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| Short-Term Borrowings     | NOTE 6 – SHORT-TERM BORROWINGS Short-term borrowings outstanding as of December 31, were comprised of the following: (Millions of dollars) 2011  2010  2009    Balance  Avg. Rate  Balance  Avg. Rate  Balance  Avg. Rate                     Commercial paper, net $2,818   1.0%  $2,710   1.5%  $2,233   1.3% Bank Borrowings  527   7.3%   479   4.9%   793(1)  5.7% Variable denomination floating rate demand notes  550   0.9%   663   1.1%   695   2.0% Total $3,895      $3,852      $3,721                               (1)Includes an $11 million short-term note, net.  |

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| - Definition
This element may be used as a single block of text to encapsulate the entire disclosure for short-term borrowings including data and tables.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 7Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19 -Article 5Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 13 -Article 9
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