Restructuring (Details) $ in Millions	6 Months Ended
	Jun. 30, 2018 USD ($)
Restructuring Cost and Reserve [Line Items]
Restructuring activities duration	18 months
Restructuring Reserve [Roll Forward]
Balance as of December 31, 2017	$ 32.0
Employee-related costs incurred	7.0
Paid during the period	(10.3)
Restructuring charges as of June 30, 2018	28.7
Operating Segments | Aviation segment
Restructuring Reserve [Roll Forward]
Balance as of December 31, 2017	0.7
Employee-related costs incurred	0.8
Paid during the period	(0.4)
Restructuring charges as of June 30, 2018	1.1
Operating Segments | Land segment
Restructuring Reserve [Roll Forward]
Balance as of December 31, 2017	25.0
Employee-related costs incurred	3.6
Paid during the period	(5.2)
Restructuring charges as of June 30, 2018	23.4
Operating Segments | Marine segment
Restructuring Reserve [Roll Forward]
Balance as of December 31, 2017	1.3
Employee-related costs incurred	1.1
Paid during the period	(0.9)
Restructuring charges as of June 30, 2018	1.5
Corporate
Restructuring Reserve [Roll Forward]
Balance as of December 31, 2017	5.0
Employee-related costs incurred	1.5
Paid during the period	(3.8)
Restructuring charges as of June 30, 2018	$ 2.7