REPORTABLE SEGMENTS (Details) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($) segment	Sep. 30, 2016 USD ($)
Segment results
Number of segments \| segment			2
Operating Revenue	$ 543.9	$ 500.4	$ 1,530.8	$ 1,422.3
Operating Income	61.8	46.7	124.1	117.4
Interest expense, net	(6.2)	(6.0)	(18.8)	(17.4)
Income before Income Taxes	55.6	40.7	105.3	100.0
Income taxes	(21.5)	(15.4)	(40.2)	(38.6)
Net Income	34.1	25.3	65.1	61.4
Operating segments
Segment results
Operating Income	61.8	46.7	124.1	117.4
Intersegment Eliminations
Segment results
Operating Revenue	12.6	6.7	32.0	10.3
Ocean Transportation \| Operating segments
Segment results
Operating Revenue	419.2	398.0	1,181.9	1,135.0
Operating Income	54.6	43.2	108.1	110.1
Logistics \| Operating segments
Segment results
Operating Revenue	124.7	102.4	348.9	287.3
Operating Income	$ 7.2	$ 3.5	$ 16.0	$ 7.3

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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