| **Long-Term Debt**                          | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
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| **Long-term Debt, Unclassified [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| Long-Term Debt                              | LONG-TERM DEBT During 2014, we issued $5.84 billion of medium-term notes, of which $4.46 billion were at fixed interest rates and $1.38 billion were at floating interest rates, primarily indexed to LIBOR.  At December 31, 2014, the outstanding medium-term notes had remaining maturities ranging up to 12 years. Long-term debt outstanding as of December 31, was comprised of the following: (Millions of dollars)        2014 2013 2012  Balance Avg. Rate Balance Avg. Rate Balance Avg. RateMedium-term notes $23,094 2.4% $23,854 2.8% $23,500 3.2%Unamortized discount (4)   (8)   (13)  Medium-term notes, net 23,090   23,846   23,487  Bank borrowings 1,484 3.4% 1,483 3.2% 1,602 4.1%Total $24,574   $25,329   $25,089                Long-term debt outstanding as of December 31, 2014, matures as follows: (Millions of dollars) 2015$6,28320165,50720175,48720182,41120192,381Thereafter2,505Total$24,574   |

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| - Definition
The entire disclosure for long-term debt.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5
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