Property and Equipment (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 1,806.9	$ 1,558.5
Accumulated depreciation and amortization	(1,166.0)	(1,027.5)
Property and equipment, net	640.9	531.0
Amortization	20.5	19.6	$ 20.7
Land
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	56.7	51.4
Buildings
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	220.5	196.4
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	205.5	187.5
Vehicles
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	490.9	394.5
Capitalized software(a)
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	199.3	179.1
Other machinery and equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 634.0	$ 549.6