| **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 Available-for-sale securities Total        Three Months Ended June 30, 2015       Balance at March 31, 2015$(760) $(3) $— $(763)Other comprehensive income/(loss) before reclassifications134 — — 134Amounts reclassified from accumulated other comprehensive (income)/loss— 1 — 1Other comprehensive income/(loss)134 1 — 135Balance at June 30, 2015$(626) $(2) $— $(628)        Three Months Ended June 30, 2016       Balance at March 31, 2016$(725) $1 $— $(724)Other comprehensive income/(loss) before reclassifications(65) (4) (2) (71)Amounts reclassified from accumulated other comprehensive (income)/loss— 4 — 4Other comprehensive income/(loss)(65) — (2) (67)Balance at June 30, 2016$(790) $1 $(2) $(791)        Six Months Ended June 30, 2015       Balance at December 31, 2014$(359) $(5) $— $(364)Other comprehensive income/(loss) before reclassifications(267) 1 — (266)Amounts reclassified from accumulated other comprehensive (income)/loss— 2 — 2Other comprehensive income/(loss)(267) 3 — (264)Balance at June 30, 2015$(626) $(2) $— $(628)        Six Months Ended June 30, 2016       Balance at December 31, 2015$(897) $— $— $(897)Other comprehensive income/(loss) before reclassifications107 (5) (2) 100Amounts reclassified from accumulated other comprehensive (income)/loss— 6 — 6Other comprehensive income/(loss)107 1 (2) 106Balance at June 30, 2016$(790) $1 $(2) $(791)         |
| 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 EndedJune 30, Six Months EndedJune 30, Classification of income (expense) 2016 2015 2016 2015Cross currency contractsOther income (expense) $(6) $— $(6) $—Interest rate contractsInterest expense (1) (2) (3) (3)Reclassifications before tax  (7) (2) (9) (3)Tax (provision) benefit  3 1 3 1Total reclassifications from Accumulated other comprehensive income/(loss) $(4) $(1) $(6) $(2)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |

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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.
+ Details**Name:**us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTableTextBlock**Namespace Prefix:**us-gaap_**Data Type:**nonnum:textBlockItemType**Balance Type:**na**Period Type:**duration |
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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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