GOODWILL, RADIO BROADCASTING LICENSES AND OTHER INTANGIBLE ASSETS (Details 4) - USD ($) $ in Millions	Dec. 31, 2018	Oct. 01, 2018	Dec. 31, 2017	Oct. 01, 2017
Schedule of Goodwill, Radio Broadcasting Licenses And Other Intangible Assets [Line Items]
Impairment charge (in millions)	$ 21.3		$ 29.1
Digital Segment [Member]
Schedule of Goodwill, Radio Broadcasting Licenses And Other Intangible Assets [Line Items]
Impairment charge (in millions)		$ 0.0		$ 0.0
Discount Rate		13.50%		13.00%
Year 1 Revenue Growth Rate		12.60%		24.10%
Digital Segment [Member] | Maximum [Member]
Schedule of Goodwill, Radio Broadcasting Licenses And Other Intangible Assets [Line Items]
Long-term Revenue Growth Rate (Years 6 – 10)		3.70%		4.30%
Operating Profit Margin Range		15.70%		17.00%
Digital Segment [Member] | Minimum [Member]
Schedule of Goodwill, Radio Broadcasting Licenses And Other Intangible Assets [Line Items]
Long-term Revenue Growth Rate (Years 6 – 10)		3.10%		2.40%
Operating Profit Margin Range		(1.10%)		(1.50%)