PROPERTY AND EQUIPMENT (Details) $ in Millions	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2019 USD ($) item	Jun. 30, 2019 USD ($) item	Dec. 31, 2018 USD ($)
Property and equipment
Cost	$ 2,603.4	$ 2,603.4	$ 2,615.2
Less: Accumulated Depreciation	(1,204.7)	(1,204.7)	(1,248.6)
Property and equipment, net	1,398.7	1,398.7	1,366.6
Vessels
Property and equipment
Cost	1,629.6	1,629.6	1,489.2
Capitalized Interest
Interest Costs Capitalized	9.9
Transfer amount to Property and Equipment	211.8
Containers and equipment
Property and equipment
Cost	516.5	516.5	513.6
Terminal facilities and other property
Property and equipment
Cost	66.1	66.1	66.0
Vessel construction in progress
Property and equipment
Cost	$ 309.8	309.8	487.2
Capitalized Interest
Interest Costs Capitalized		$ 14.4	16.3
Number of vesels under agreements for contstruction \| item	2	2
Other construction in progress
Property and equipment
Cost	$ 81.4	$ 81.4	$ 59.2

Number of vessels under agreements for construction.

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Amount of increase (decrease) of physical assets used in the normal conduct of business and not intended for resale, from reclassification, impairment, donation, or changes classified as other. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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