SIGNIFICANT ACCOUNTING POLICIES - PROPERTY AND EQUIPMENT (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Jun. 30, 2017	Dec. 31, 2016
Property and equipment
Cost	$ 2,230.8	$ 2,151.9
Less: Accumulated Depreciation	(1,241.8)	(1,202.7)
Property and equipment, net	989.0	949.2
Vessels
Property and equipment
Cost	1,423.9	1,416.1
Containers and equipment
Property and equipment
Cost	544.0	536.9
Terminal facilities and other property
Property and equipment
Cost	57.8	43.2
Vessel construction in progress
Property and equipment
Cost	170.7	124.5
Capitalized Interest
Interest Costs Capitalized	5.5	2.9
Other construction in progress
Property and equipment
Cost	$ 34.4	$ 31.2

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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