SIGNIFICANT ACCOUNTING POLICIES - INVESTMENT IN TERMINAL JOINT VENTURE (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Investments in affiliates
Investment in Terminal Joint Venture	$ 96.7		$ 93.2
Financial information for equity method investment
Company Share of Net Income	10.5	$ 4.9
SSAT
Financial information for equity method investment
Operating revenue	250.9	196.7
Operating costs and expenses	(219.7)	(184.0)
Operating Income	31.2	12.7
Net Income	$ 30.7	$ 14.3

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The amount of the cost of sales reported by an equity method investment of the entity.

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The amount of gross profit (loss) reported by an equity method investment of the entity.

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Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership.

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