| **Fair Value Measurements (Tables)**  | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
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| **Fair Value Disclosures [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| Fair values of financial instruments  | Please refer to the table below for the fair values of our financial instruments.(Millions of dollars) 2015 2014    Carrying Amount Fair Value Carrying Amount Fair ValueFair Value LevelsReferenceCash and cash equivalents $1,016 $1,016 $857 $8571 Foreign currency contracts:          In a receivable position $3 $3 $5 $52Note 10In a payable position $(6) $(6) $(15) $(15)2Note 10Cross currency contracts          In a receivable position $37 $37 $17 $172Note 10Finance receivables, net (excluding finance leases(1)) $20,935 $20,925 $21,434 $21,0933Note 3Restricted cash and cash equivalents(2) $18 $18 $11 $111 Short-term borrowings $(6,958) $(6,958) $(4,699) $(4,699)1Note 8Long-term debt $(21,605) $(21,904) $(24,574) $(25,103)2Note 9Interest rate swaps:          In a net receivable position $51 $51 $79 $792Note 10In a net payable position $(4) $(4) $(8) $(8)2Note 10Guarantees $— $— $(1) $(1)3Note 11           (1) As of December 31, 2015 and 2014, represents finance leases with a net carrying value of $6.45 billionand$7.64 billion, respectively.(2) Included in Other assets in the Consolidated Statements of Financial Position. |

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| - Definition
Tabular disclosure of the fair value of financial instruments, including financial assets and financial liabilities, and the measurements of those instruments, assets, and liabilities.
+ References
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| - References
No definition available.
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