Property and Equipment (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 384.0	$ 319.4
Less: Accumulated depreciation and amortization	(189.3)	(159.9)
Total property and equipment, net	194.7	159.5
Depreciation and amortization expenses	28.9	26.0	$ 21.5
Delivery, warehouse and office equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	280.4	235.3
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	68.6	54.4
Land and buildings
Property, Plant and Equipment [Line Items]
Property and equipment, gross	32.0	28.9
Construction in progress
Property, Plant and Equipment [Line Items]
Property and equipment, gross	3.0	0.8
Equipment capital leases
Property, Plant and Equipment [Line Items]
Property and equipment, gross	13.5	13.4
Warehouse equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 4.8	$ 4.8