REPORTABLE SEGMENTS (Details) $ in Millions	3 Months Ended
Mar. 31, 2018 USD ($) segment	Mar. 31, 2017 USD ($)
Segment results
Number of segments \| segment	2
Operating Revenue	$ 511.4	$ 474.4
Operating Income	28.7	17.2
Interest expense, net	(5.0)	(6.3)
Other income (expense), net	0.8	(0.8)
Income before Income Taxes	24.5	10.1
Income taxes	(10.3)	(3.1)
Net Income	14.2	7.0
Equity in income of Terminal Joint Venture	10.5	4.9
Operating segments
Segment results
Operating Income	28.7	17.2
Intersegment Eliminations
Segment results
Operating Revenue	18.3	16.9
Ocean Transportation \| Operating segments
Segment results
Operating Revenue	379.3	370.0
Operating Income	24.5	15.3
Logistics \| Operating segments
Segment results
Operating Revenue	132.1	104.4
Operating Income	$ 4.2	$ 1.9

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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