SIGNIFICANT ACCOUNTING POLICIES - INVESTMENT IN SSAT (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Investments in affiliates
Investment in Terminal Joint Venture	$ 92.7		$ 58.7
Financial information for equity method investment
Company Share of Net Income	34.0	$ 9.2
Ocean Transportation
Financial information for equity method investment
Company Share of Net Income	34.0	9.2
SSAT
Investments in affiliates
Investment in Terminal Joint Venture	92.7		$ 58.7
Financial information for equity method investment
Operating revenue	430.4	306.1
Operating costs and expenses	(306.9)	(273.1)
Operating Income	123.5	33.0
Net Income	100.1	28.9
Company Share of Net Income	$ 34.0	$ 9.2

The aggregate cost of goods produced and sold and services rendered during the reporting period.

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