PROPERTY AND EQUIPMENT - SUMMARY (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Property and equipment
Property and Equipment	$ 3,087.4	$ 2,912.3
Accumulated depreciation	1,209.1	1,222.4
Property and equipment, net	1,878.3	1,689.9
Depreciation Expense	117.1	97.1	$ 86.3
Vessels
Property and equipment
Property and Equipment	2,243.8	2,191.6
Accumulated depreciation	760.5	785.5
Property and equipment, net	1,483.3	1,406.1
Containers and equipment
Property and equipment
Property and Equipment	680.9	572.3
Accumulated depreciation	399.4	391.8
Property and equipment, net	281.5	180.5
Terminal facilities and other property
Property and equipment
Property and Equipment	128.3	119.8
Accumulated depreciation	49.2	45.1
Property and equipment, net	79.1	74.7
Vessel construction in progress
Property and equipment
Property and Equipment	14.9
Property and equipment, net	14.9
Other construction in progress
Property and equipment
Property and Equipment	19.5	28.6
Property and equipment, net	$ 19.5	$ 28.6

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

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