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Summary of Significant Accounting Policies - Basis of Presentation (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
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Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Disposal Group, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |
Sales | $ 909.9 | $ 869.1 | $ 880.2 | $ 865.9 | $ 796.1 | $ 770.5 | $ 810.5 | $ 757.5 | $ 3,525.1 | $ 3,134.6 | $ 3,719.6

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- Definition Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1(a)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
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