Business Segments - Income Statement Items (Details) $ in Millions	3 Months Ended
Mar. 31, 2020 USD ($) segment	Mar. 31, 2019 USD ($)
Information concerning revenue, gross profit and income from operations by segment
Number of reportable operating business segments \| segment	3
Revenue:
Revenue	$ 8,015.2	$ 8,678.8
Gross profit:
Gross profit	258.7	251.1
Income from operations:
Income from operations	70.8	70.4
Operating Segments
Income from operations:
Income from operations	88.6	90.1
Corporate
Income from operations:
Income from operations	(17.8)	(19.7)
Aviation segment
Revenue:
Revenue	3,764.1	4,252.7
Gross profit:
Gross profit	93.2	114.3
Aviation segment \| Operating Segments
Income from operations:
Income from operations	29.1	55.6
Land segment
Revenue:
Revenue	2,106.0	2,493.6
Gross profit:
Gross profit	106.3	101.5
Land segment \| Operating Segments
Income from operations:
Income from operations	25.7	21.0
Marine segment
Revenue:
Revenue	2,145.0	1,932.5
Gross profit:
Gross profit	59.3	35.2
Marine segment \| Operating Segments
Income from operations:
Income from operations	$ 33.9	$ 13.5

Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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