| **Accumulated Other Comprehensive Income/(Loss)**                        | 3 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
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| **Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
| Accumulated Other Comprehensive Income/(Loss)                            | Accumulated Other Comprehensive Income/(Loss) Comprehensive income/(loss) and its components are presented in the Consolidated Statements of Comprehensive Income.  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 March 31, 2014     Balance at December 31, 2013$122 $(5) $117Other comprehensive income/(loss) before reclassifications5 (2) 3Amounts reclassified from accumulated other comprehensive income/(loss)— 1 1Other comprehensive income/(loss)5 (1) 4Balance at March 31, 2014$127 $(6) $121      Three Months Ended March 31, 2015     Balance at December 31, 2014$(359) $(5) $(364)Other comprehensive income/(loss) before reclassifications(401) 1 (400)Amounts reclassified from accumulated other comprehensive income/(loss)— 1 1Other comprehensive income/(loss)(401) 2 (399)Balance at March 31, 2015$(760) $(3) $(763)      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 March 31, Classification of income (expense) 2015 2014Foreign exchange contractsOther income (expense) $— $—Interest rate contractsInterest expense (1) (1)Reclassifications before tax  (1) (1)Tax (provision) benefit  — —Total reclassifications from Accumulated other comprehensive income/(loss)  $(1) $(1)       |

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| - Definition
The entire disclosure for comprehensive income, which includes, but is not limited to, 1) the amount of income tax expense or benefit allocated to each component of other comprehensive income, including reclassification adjustments, 2) the reclassification adjustments for each classification of other comprehensive income and 3) the ending accumulated balances for each component of comprehensive income.
+ References
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