REPORTABLE SEGMENTS (Details) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) segment	Sep. 30, 2015 USD ($)
Segment results
Number of segments \| segment			2
Operating Revenue	$ 500.4	$ 544.3	$ 1,422.3	$ 1,390.1
Operating Income	46.2	71.8	116.9	150.4
Interest expense	(6.0)	(4.7)	(17.4)	(13.6)
Income before Income Taxes	40.2	67.1	99.5	136.8
Income taxes	(15.2)	(25.6)	(38.4)	(60.4)
Net Income	25.0	41.5	61.1	76.4
Operating segments
Segment results
Operating Income	46.2	71.8	116.9	150.4
Intersegment Eliminations
Segment results
Operating Revenue	6.7	3.4	10.3	8.9
Ocean Transportation \| Operating segments
Segment results
Operating Revenue	398.0	444.8	1,135.0	1,097.0
Operating Income	42.7	68.9	109.6	144.2
Logistics \| Operating segments
Segment results
Operating Revenue	102.4	99.5	287.3	293.1
Operating Income	$ 3.5	$ 2.9	$ 7.3	$ 6.2

This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

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