| **Short-Term Borrowings (Tables)** | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
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| **Short-term Debt [Abstract]**     |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| Short-term borrowings              | Short-term borrowings outstanding as of December 31, were comprised of the following: (Millions of dollars)        2012 2011 2010  Balance Avg. Rate Balance Avg. Rate Balance Avg. RateCommercial paper, net $3,654 0.6% $2,818 1.0% $2,710 1.5%Bank borrowings 418 5.6% 527 7.3% 479 4.9%Variable denomination floating    rate demand notes 579 0.8% 550 0.9% 663 1.1%Total $4,651   $3,895   $3,852                |

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| - Definition
Tabular disclosure of short-term debt arrangements (having initial terms of repayment within one year or the normal operating cycle, if longer) including: (1) description of the short-term debt arrangement; (2) identification of the lender or type of lender; (3) repayment terms; (4) weighted average interest rate; (5) carrying amount of funds borrowed under the specified short-term debt arrangement as of the balance sheet date; (6) description of the refinancing of a short-term obligation when that obligation is excluded from current liabilities in the balance sheet; and (7) amount of a short-term obligation that has been excluded from current liabilities in the balance sheet because of a refinancing of the obligation.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19 -Article 5Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682
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| - Details**Name:**us-gaap_ShortTermBorrowingsAbstract**Namespace Prefix:**us-gaap_**Data Type:**xbrli:stringItemType**Balance Type:**na**Period Type:**duration |