|**Summary of Significant Accounting Policies (Tables)**                             | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                       
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|**Organization, Consolidation and Presentation of Financial Statements [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                       
|Accumulated Other Comprehensive Income/(Loss)                                       | Accumulated other comprehensive income/(loss), net of tax, included in the Consolidated Statements of Changes in Stockholder's Equity, consisted of the following as of:(Millions of dollars)December 31,201220112010Foreign currency translation$184$122$231Derivative financial instruments(8)(6)(14)Total Accumulated other comprehensive income/(loss)$176$116$217
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|Foreign currency translation                                                        |                                                                                                                                                                                                                                                                                                                                                                       
|Derivative financial instruments                                                    |                                                                                                                                                                                                                                                                                                                                                                       
|Total Accumulated other comprehensive income/(loss)                                 |                                                                                                                                                                                                                                                                                                                                                                       
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                    duration X- DefinitionTabular disclosure of the components of accumulated other comprehensive income (loss).+ ReferencesReference 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=20435746&loc=SL7669686-108580+ Details**Name:**
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