Impact of Recently Issued Accounting Guidance (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Impact of Recently Issued Accounting Standards—Adopted
Warehouse, delivery, selling, general and administrative	$ 476.2	$ 449.5
Other expense, net	$ 4.4	0.2
Impact of Recently Issued Accounting Standards—Adopted \| Improvements to Employee Share-Based Payment Accounting
Impact of Recently Issued Accounting Standards—Adopted
Warehouse, delivery, selling, general and administrative		(1.3)
Other expense, net		$ 1.3

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Amount of income (expense) related to nonoperating activities, classified as other.

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

+ 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 210.5-03.4)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
-SubTopic 10
-Section 30
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=68048583&loc=d3e3636-108311

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