| **Inventories**                     | 6 Months Ended                                                                                                                                                                                                                                                                                                           |
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| **Inventory Disclosure [Abstract]** |                                                                                                                                                                                                                                                                                                                     |
| Inventories                         | 7. InventoriesInventories are stated at the lower of cost or market value. The components of inventories were as follows:(in millions of dollars)June 30, 2016 December 31, 2015Raw materials$39.7 $33.3Work in process3.6 2.6Finished goods259.9 167.7Total inventories$303.2 $203.6 |

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| - References
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| - Definition
The entire disclosure for inventory. This may include, but is not limited to, the basis of stating inventory, the method of determining inventory cost, the major classes of inventory, and the nature of the cost elements included in inventory. If inventory is stated above cost, accrued net losses on firm purchase commitments for inventory and losses resulting from valuing inventory at the lower-of-cost-or-market may also be included. For LIFO inventory, may disclose the amount and basis for determining the excess of replacement or current cost over stated LIFO value and the effects of a LIFO quantities liquidation that impacts net income.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.6) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6361739&loc=d3e7789-107766Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 6 -Subparagraph a, b, c -Article 5
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