Business Segments, Geographic Information, and Major Customers - Income Statement Items (Details) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2016 USD ($) segment	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Information concerning revenue, gross profit and income from operations by segment
Number of reportable operating business segments | segment									3
Revenue:
Revenue	$ 7,792.1	$ 7,399.8	$ 6,633.0	$ 5,190.8	$ 6,733.6	$ 7,810.7	$ 8,496.4	$ 7,340.7	$ 27,015.8	$ 30,381.4	$ 43,391.8
Gross profit:
Gross profit	$ 222.3	$ 236.7	$ 218.5	$ 221.5	$ 230.2	$ 226.7	$ 190.4	$ 213.6	899.0	861.0	819.1
Income from operations:
Income from operations									188.9	245.7	276.7
Depreciation and amortization:
Depreciation and amortization									82.3	65.5	57.3
Capital expenditures:
Total capital expenditures									37.7	48.4	51.8
Aviation segment
Revenue:
Revenue									10,914.4	11,739.8	17,268.8
Gross profit:
Gross profit									401.0	361.9	323.4
Marine segment
Revenue:
Revenue									7,182.5	9,367.2	13,843.3
Gross profit:
Gross profit									149.5	189.6	207.8
Land segment
Revenue:
Revenue									8,918.8	9,274.3	12,279.6
Gross profit:
Gross profit									348.5	309.5	287.9
Operating Segments
Income from operations:
Income from operations									261.5	306.5	330.2
Operating Segments | Aviation segment
Income from operations:
Income from operations									160.5	132.2	144.1
Depreciation and amortization:
Depreciation and amortization									24.2	22.6	15.4
Capital expenditures:
Total capital expenditures									4.9	13.4	9.0
Operating Segments | Marine segment
Income from operations:
Income from operations									30.2	73.0	92.2
Depreciation and amortization:
Depreciation and amortization									6.6	6.4	5.6
Capital expenditures:
Total capital expenditures									6.1	8.0	13.9
Operating Segments | Land segment
Income from operations:
Income from operations									70.8	101.4	93.9
Depreciation and amortization:
Depreciation and amortization									47.1	32.9	32.5
Capital expenditures:
Total capital expenditures									12.3	16.4	16.0
Corporate
Income from operations:
Income from operations									(72.7)	(60.9)	(53.5)
Depreciation and amortization:
Depreciation and amortization									4.4	3.7	3.7
Capital expenditures:
Total capital expenditures									$ 14.5	$ 10.6	$ 12.9