| **Fair Value Of Financial Instruments (Tables)**                           | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                               |
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| **Fair Value Disclosures [Abstract]**                                      |                                                                                                                                                                                                                                                                                                                                                                                                         |
| Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis | The following table sets forth our financial assets and liabilities that were accounted for at fair value on a recurring basis as of September 30, 2017 and December 31, 2016:(in millions of dollars)September 30, 2017 December 31, 2016Assets:   Forward currency contracts$21.2 $4.4Liabilities:   Forward currency contracts$24.6 $0.3 |

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| - References
No definition available.
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| - Definition
Tabular disclosure of assets and liabilities, including [financial] instruments measured at fair value that are classified in stockholders' equity, if any, that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3).
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19190-110258
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