Business Segments - Income Statement Items (Details) $ in Millions	3 Months Ended
Mar. 31, 2021 USD ($) segment	Mar. 31, 2020 USD ($)
Information concerning revenue, gross profit and income from operations by segment
Number of reportable operating business segments \| segment	3
Revenue:
Revenue	$ 5,957.9	$ 8,015.2
Gross profit:
Gross profit	191.6	258.7
Income from operations:
Income from operations	37.6	70.8
Operating Segments
Income from operations:
Income from operations	62.1	88.6
Corporate
Income from operations:
Income from operations	(24.5)	(17.8)
Aviation segment
Revenue:
Revenue	2,095.0	3,764.1
Gross profit:
Gross profit	76.7	93.2
Aviation segment \| Operating Segments
Income from operations:
Income from operations	23.0	29.1
Land segment
Revenue:
Revenue	2,188.2	2,106.0
Gross profit:
Gross profit	89.5	106.3
Land segment \| Operating Segments
Income from operations:
Income from operations	32.8	25.7
Marine segment
Revenue:
Revenue	1,674.7	2,145.0
Gross profit:
Gross profit	25.4	59.3
Marine segment \| Operating Segments
Income from operations:
Income from operations	$ 6.4	$ 33.9

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

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