PROPERTY AND EQUIPMENT - Schedule of Property and Equipment (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 2,203.5	$ 2,175.2
Less accumulated depreciation	(386.1)	(304.8)
Property and equipment, net	1,817.4	1,870.4
Land and freehold buildings
Property, Plant and Equipment [Line Items]
Property and equipment, gross	90.7	14.1
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	6.7	6.4
Fiber optic cable
Property, Plant and Equipment [Line Items]
Property and equipment, gross	702.2	777.9
Duct
Property, Plant and Equipment [Line Items]
Property and equipment, gross	686.1	669.6
Fiber optic network equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	613.9	582.9
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	62.3	58.1
Computer hardware and software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 41.6	$ 66.2

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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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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