| **Accumulated Other Comprehensive Income/(Loss) (Tables)**               | 6 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 June 30, 2013     Balance at March 31, 2013$80 $(7) $73Other comprehensive income/(loss) before reclassifications(63) 2 (61)Amounts reclassified from accumulated other comprehensive income/(loss)— 1 1Other comprehensive income/(loss)(63) 3 (60)Balance at June 30, 2013$17 $(4) $13      Three Months Ended June 30, 2014     Balance at March 31, 2014$127 $(6) $121Other comprehensive income/(loss) before reclassifications32 (2) 30Amounts reclassified from accumulated other comprehensive income/(loss)— 1 1Other comprehensive income/(loss)32 (1) 31Balance at June 30, 2014$159 $(7) $152      Six Months Ended June 30, 2013     Balance at December 31, 2012$184 $(8) $176Other comprehensive income/(loss) before reclassifications(167) 2 (165)Amounts reclassified from accumulated other comprehensive income/(loss)— 2 2Other comprehensive income/(loss)(167) 4 (163)Balance at June 30, 2013$17 $(4) $13      Six Months Ended June 30, 2014     Balance at December 31, 2013$122 $(5) $117Other comprehensive income/(loss) before reclassifications37 (4) 33Amounts reclassified from accumulated other comprehensive income/(loss)— 2 2Other comprehensive income/(loss)37 (2) 35Balance at June 30, 2014$159 $(7) $152       |
| 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 Ended June 30, Six Months Ended June 30, Classification of income (expense) 2014 2013 2014 2013Foreign exchange contractsOther income (expense) $— $— $— $—Interest rate contractsInterest expense (1) (2) (2) (3)Reclassifications before tax  (1) (2) (2) (3)Tax (provision) benefit  — 1 — 1Total reclassifications from Accumulated other comprehensive income/(loss)  $(1) $(1) $(2) $(2)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |

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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=28358780&loc=SL7669686-108580
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