GOODWILL AND OTHER INTANGIBLE ASSETS - INTANGIBLE ASSETS SUBJECT TO AMORTIZATION (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2018	Dec. 31, 2017	Sep. 25, 2018
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 16,257.5	$ 16,083.0
Accumulated Amortization	(4,775.8)	(4,299.7)
Net Book Value	11,481.7	11,783.3
Acquired network location intangibles
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	4,840.2	4,858.8
Accumulated Amortization	(1,669.2)	(1,525.3)
Net Book Value	$ 3,171.0	$ 3,333.5
Acquired network location intangibles | Maximum
Finite-Lived Intangible Assets [Line Items]
Estimated Useful Lives	20 years	20 years
Acquired tenant-related intangibles
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 11,337.5	$ 11,150.9
Accumulated Amortization	(3,092.8)	(2,754.7)
Net Book Value	$ 8,244.7	8,396.2
Acquired tenant-related intangibles | Minimum
Finite-Lived Intangible Assets [Line Items]
Estimated Useful Lives	15 years
Acquired tenant-related intangibles | Maximum
Finite-Lived Intangible Assets [Line Items]
Estimated Useful Lives	20 years
Acquired licenses and other intangibles
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 79.8	58.8
Accumulated Amortization	(13.8)	(8.1)
Net Book Value	$ 66.0	50.7
Acquired licenses and other intangibles | Minimum
Finite-Lived Intangible Assets [Line Items]
Estimated Useful Lives	3 years
Acquired licenses and other intangibles | Maximum
Finite-Lived Intangible Assets [Line Items]
Estimated Useful Lives	20 years
Economic Rights, TV Azteca
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 0.0	14.5
Accumulated Amortization	0.0	(11.6)
Net Book Value	$ 0.0	$ 2.9	$ 3.0
Estimated Useful Lives	70 years