Basis of Presentation Basis of Presentation (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Jan. 01, 2018	Dec. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Increase in costs of sales	$ 521.2	$ 429.5
Decrease in inventories	406.5			$ 349.3
Increase in other current assets	69.6			$ 19.6
ASC 606
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Contract with Customer, Asset, Gross			$ 28.1
Contract with customer asset, net	46.4		22.1
ASC 606 Deferred Tax Liability			2.3
Contract with customer, asset, reduced inventories			19.1
ASC 606 | Difference between Revenue Guidance in Effect before and after Topic 606
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Increase in revenues from contracts with customers	12.4
Increase in costs of sales	9.7
Decrease in inventories	37.7
Increase in other current assets	46.4
ASC 606 | Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect of new accounting principle in period of adoption			$ 6.7
Change resulting from ASU No. 2017-07 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect of new accounting principle in period of adoption	$ 5.2	$ 3.3