Inventory Financing Agreements (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Inventory Financing Agreements [Line Items]
Accounts payable-inventory financing	$ 523.7	$ 498.0
Accounts Payable, Inventory Financing
Inventory Financing Agreements [Line Items]
Revolving Loan inventory financing agreement	481.6	480.9
Other inventory financing agreements	$ 42.1	$ 17.1