SIGNIFICANT ACCOUNTING POLICIES - RECOGNITION OF REVENUES AND EXPENSES (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Total	$ 557.9	$ 557.1	$ 1,090.3	$ 1,068.5
Ocean Transportation
Ocean Transportation services	406.6	397.3	794.5	766.1
Terminal and other related services	4.8	5.0	11.5	11.2
Fuel sales	2.6	2.5	4.6	5.1
Vessel management services and related costs	1.4	1.8	$ 2.7	$ 3.5
Percentage of ocean transportation revenues and fuel sales denominated in foreign currency			3.00%	3.00%
Total	415.4	406.6	$ 813.3	$ 785.9
Logistics
Transportation Brokerage and Freight Forwarding Services	134.7	143.0	261.1	267.5
Warehouse and distribution services	5.3	4.2	10.6	8.8
Supply chain management and other services	2.5	3.3	5.3	6.3
Total	142.5	150.5	$ 277.0	$ 282.6
Percentage of transportation brokerage and freight forwarding services revenue denominated in foreign currency			3.00%	3.00%
Ocean Transportation
Total	415.4	406.6	$ 813.3	$ 785.9
Logistics
Total	$ 142.5	$ 150.5	$ 277.0	$ 282.6