PROPERTY AND EQUIPMENT (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Depreciation expense	$ 905.5	$ 883.1	$ 835.5
Amortization of right-of-use asset	168.1
Property and equipment		17,717.2
Accumulated depreciation		6,470.1
Land easements, not depreciable	1,575.2
Assets Held under Capital Leases
Property, Plant and Equipment [Line Items]
Property and equipment	3,059.7
Finance lease, right-of-use asset, accumulated amortization	$ 1,140.4
Assets Held under Capital Leases | Assets Held under Capital Leases
Property, Plant and Equipment [Line Items]
Property and equipment		4,369.5
Accumulated depreciation		$ 1,016.2