Restructuring Charges - Summary of Restructuring Reserve (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Restructuring Reserve [Roll Forward]
Reserve, beginning balance	$ 5.1
From ND Acquisition	14.3
Charges Incurred	56.9
Payments	(15.1)
Reserve, ending balance	61.2	$ 5.1
Operating Segments | Transportation
Restructuring Reserve [Roll Forward]
Reserve, beginning balance	0.0
From ND Acquisition	4.9
Charges Incurred	28.1
Payments	(5.6)
Reserve, ending balance	27.4	0.0
Operating Segments | Transportation | Contract termination
Restructuring Reserve [Roll Forward]
Reserve, beginning balance	0.0
From ND Acquisition	0.1
Charges Incurred	0.0
Payments	0.0
Reserve, ending balance	0.1	0.0
Operating Segments | Transportation | Facilities
Restructuring Reserve [Roll Forward]
Reserve, beginning balance	0.0
From ND Acquisition	0.0
Charges Incurred	0.8
Payments	(0.2)
Reserve, ending balance	0.6	0.0
Operating Segments | Transportation | Severance
Restructuring Reserve [Roll Forward]
Reserve, beginning balance	0.0
From ND Acquisition	4.8
Charges Incurred	27.3
Payments	(5.4)
Reserve, ending balance	26.7	0.0
Operating Segments | Logistics
Restructuring Reserve [Roll Forward]
Reserve, beginning balance	0.0
From ND Acquisition	9.4
Charges Incurred	22.2
Payments	(5.3)
Reserve, ending balance	26.3	0.0
Operating Segments | Logistics | Contract termination
Restructuring Reserve [Roll Forward]
Reserve, beginning balance	0.0
From ND Acquisition	0.1
Charges Incurred	0.9
Payments	(0.2)
Reserve, ending balance	0.8	0.0
Operating Segments | Logistics | Severance
Restructuring Reserve [Roll Forward]
Reserve, beginning balance	0.0
From ND Acquisition	9.3
Charges Incurred	21.3
Payments	(5.1)
Reserve, ending balance	25.5	0.0
Corporate
Restructuring Reserve [Roll Forward]
Reserve, beginning balance	5.1	0.0
From ND Acquisition	0.0
Charges Incurred	6.6	11.4
Payments	(4.2)	(6.3)
Reserve, ending balance	7.5	5.1
Corporate | Contract termination
Restructuring Reserve [Roll Forward]
Reserve, beginning balance	3.8	0.0
From ND Acquisition	0.0
Charges Incurred	3.3	6.0
Payments	(3.1)	(2.2)
Reserve, ending balance	4.0	3.8
Corporate | Severance
Restructuring Reserve [Roll Forward]
Reserve, beginning balance	1.3	0.0
From ND Acquisition	0.0
Charges Incurred	3.3	5.4
Payments	(1.1)	(4.1)
Reserve, ending balance	$ 3.5	$ 1.3