| **Accumulated Other Comprehensive Income/(Loss) (Tables)**               | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
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| **Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| Schedule of Accumulated other comprehensive income/(loss)                | Changes in Accumulated other comprehensive income/(loss), net of tax, included in the Consolidated Statements of Changes in Stockholder's Equity, consisted of the following:(Millions of dollars)Foreign currency translation Derivative financial instruments Total      Three Months Ended September 30, 2014     Balance at June 30, 2014$159 $(7) $152Other comprehensive income/(loss) before reclassifications(316) (1) (317)Amounts reclassified from accumulated other comprehensive (income)/loss— 1 1Other comprehensive income/(loss)(316) — (316)Balance at September 30, 2014$(157) $(7) $(164)      Three Months Ended September 30, 2015     Balance at June 30, 2015$(626) $(2) $(628)Other comprehensive income/(loss) before reclassifications(200) (1) (201)Amounts reclassified from accumulated other comprehensive (income)/loss— 1 1Other comprehensive income/(loss)(200) — (200)Balance at September 30, 2015$(826) $(2) $(828)      Nine Months Ended September 30, 2014     Balance at December 31, 2013$122 $(5) $117Other comprehensive income/(loss) before reclassifications(279) (5) (284)Amounts reclassified from accumulated other comprehensive (income)/loss— 3 3Other comprehensive income/(loss)(279) (2) (281)Balance at September 30, 2014$(157) $(7) $(164)      Nine Months Ended September 30, 2015     Balance at December 31, 2014$(359) $(5) $(364)Other comprehensive income/(loss) before reclassifications(467) — (467)Amounts reclassified from accumulated other comprehensive (income)/loss— 3 3Other comprehensive income/(loss)(467) 3 (464)Balance at September 30, 2015$(826) $(2) $(828)       |
| Reclassifications out of Accumulated other comprehensive income/(loss)   | The effect of the reclassifications out of Accumulated other comprehensive income/(loss) on the Consolidated Statements of Profit was as follows:(Millions of dollars)  Three Months EndedSeptember 30, Nine Months EndedSeptember 30, Classification of income (expense) 2015 2014 2015 2014Foreign exchange contractsOther income (expense) $— $— $— $—Interest rate contractsInterest expense (1) (2) (4) (4)Reclassifications before tax  (1) (2) (4) (4)Tax (provision) benefit  — 1 1 1Total reclassifications from Accumulated other comprehensive income/(loss)  $(1) $(1) $(3) $(3)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |

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| - References
No definition available.
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| - Definition
Tabular disclosure of information about items reclassified out of accumulated other comprehensive income (loss).
+ References
No definition available.
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| - Definition
Tabular disclosure of the components of accumulated other comprehensive income (loss).
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669686-108580
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